I think I have the perfect stories for you, but both of them are mangas. The first one is called "The 100 Girlfriends Who Really, Really, Really, Really, Really Love You". I know that the title sounds ridiculous but trust me, this one is a gem and is exactly what you are looking for. It has A LOT of fluff, every girl in the harem gets a lot of attention and is never forgotten. I would recommend you to read it on mangahub because of some problems with the scanlation group many sites don't have all the chapters and mangahub has all of them. The second one is called "Kanojo mo Kanojo" and is also very sweet. Both of them are real harems, have a lot of fluff, and are really funny. I really recommend you to check them out!
Looking for mostly "happy/fluffy" harem stories
Leporidere Thanks! Overall i highly prefer flow text and mangas aren't really my thing. But those two really look cute and since i don't have much else to read i'll definitely gonna try them!
(And thanks for the source recommendation as well =D )
OK, to start this one isn't fuffy and there is a part or two that get you excited. but it's a pretty fun story.
it's only got 10 chapter's so far, but I post new ones every day along with my other harem book which I'll post below that is at 50 chapters so far. Hopefully, you're not looking for something PG either lol.
The Delinquent and Transmigration God/ Summoned to another world
Restricted/R-18/Sexual content/Strong Language
Don't f#$% with him. 17-year-old Hyde is a delinquent that meets his end in a back alley, but he is transported to another world on death.
One of many, Gripton, Transmigration God, helps Hyde to choose his magic but decides to stay and try and teach this boy some manners. He also gave Hyde a strong magical ability that could upend the world Hyde was sent to save.
These two will travel the world and take the nations and their daughters by storm. In a world where everyone has a magic skill and the strong rule, what path will the so-called hero take? Summoned to another world against his wishes, Hyde has his own way of doing things.
Join the foul-mouthed delinquent and Hopeful Transmigration god across a new land!
- Edited
Poor Man Reborn
Restricted/R-18/Sexual content/Some Strong Language
Welcome to Reborn! A place of infinite lifetimes in worlds and planes thought only to be places drawn from imagination. Players that enter this world are children stricken with a particular terminal disease and given a chance to be reborn an infinite amount of times, participating in new challenges and systems every lifetime.
Not everything is perfect, though. Reborn's creators hide the fact that players enter as NPC's and without having a supporting god, they will continue to get lost in the flow of time, losing all memories after each life. For some, they are forced to live in poverty or worse.
"Gods": Players that have won or been on the winning party at least 20 times or been granted godship through a wish.
Dave, one of the thousands of players, is a 42 years old homeless man with his memories wiped and has lived this life in poverty. One of the many gods that have transcended, Fate, stood to cross him at every turn and kept him from success. Now sitting in an alley and about to die, Dave prays to anyone listening to give him another chance.
Two gods heard this plea, for they had been watching and waiting. Destiny and Transmigration had been waiting for this moment to snatch up Fate's plaything.
As Dave gives his last dying breathes, he hopes his next life is better.
When Dave dies, the goddesses take him to a new world and explain his new leveling up system, but he realizes a horrible fact when he opens his eye.
Dave is a poor street urchin with no home. Reborn as a poor kid.
Memories of his previous life are all he has to go on, but Destiny guides him to reconnect with strangers from past lives and start him on another journey to save more lost souls. Slowly the memories with each woman reconnect and help Dave get back the experiences he lost while forming new connections and relationships along the way.
Join Dave, Lavender, Tilly, and all the rest on their adventure through worlds and as they meet new friends and experiences new systems!
https://www.webnovel.com/book/poor-man-reborn_18198360906804605
- Edited
Nebel
Here are some that I read and can recommend -
0 - Against Heaven's will -the continuation of - Spirit Cultivation
1 - Psychic Inventor in Cultivation World - flirting mostly and later++ things take a turn to romance
2 - In Naruto: Reborn with Talent = fanfic worth the read, only 46 chapters atm
3 - Prime Vampire = good plot, writing could improve but a good read + another work of the author is decent
4 - Trash Techniques are Actually Pretty Efficient = A comedic tone with the story that is a bit quirky, late harem
5 - Nine Venoms Sect Founder - good writing and plot, can be a bit confusing at times - ~150 chapt - late harem it seems
6 - Shadow - Unique cultivation + harem story, anti-hero - skim through first ~15 chapters to enjoy - medium/late romance improves as you read
7 - Perverted Otherworlder = comedy, fun, cultivation and shameless mc
8 - Yin & Yang Pleasures of Cultivation - Interesting story, plot and good writing
9 - The Romantic Cultivator - MC is funny, keep going in the beginning, the plot, story and characters are worth the read
10 - Fourth Prince's Debauchery starts off with r-18 leads to plot + author's other work (Science/magic - an unnecessary tragedy, in the beginning, is good after)
11 - The Sinful Life of The Emperor - a great read, MC 'steals' other's women, you will be happy and laughing most of the time
12 - A Cliché Multiverse Story - good fanfic story you don't need to have much previous knowledge of the worlds
13 - Stealing Spree - MC steals other's women there is a plot and generally with positive vibes, the start of the story is not very happy
14 - Unrivaled System - I read a while back, I remember enjoying it not sure how the r18 and romance in the harem is balanced.
Most are original work of here... If you have any other good ones share them.
Edit() PS the list is not in any order.
GUys idk why this pop up on webnovel just like that Your work The devil son in law is restricted!
As Chinese or Korean appears in the chapter content (or chapter title, book title, abbreviation and synopsis ), your work will not be voted and gifted. After you modify the content, please contact the platform editor for processing as soon as possible.
thats what it say can anyone explain it please.
Check out my novel if you are interested.
Godfather and Godson!
Nebel You can try mine, it's freshly start but quite a fluffy romance I'm aiming (not so harem, though--only spoils here haha)
https://dynamic.webnovel.com/book/18471140106956505?utm_source=writerShare&utm_campaign=4314653463
Hey,
honestly, i don't know if anyone is interested about my opinion about a novel that was recommended, but i just like to give some feedback :x
SecretWolf thanks for this super long list and even with some nice explanation! I thought about starting with Prime Vampire, Psychic Inventor and Romantic Cultivator.
I didn't had much time this week and only managed to read Prime Vampire to some degree. The story is quite promising, but god i hate this mc sooo much. He only cares about his owne pleasure, fucks every girl the first time they meet and treats them SO bad in bed... i really was disgusted by him. Really sad because the story could have been quite good.
I think i will try Romantic Cultivator next, i've read that the mc is quite dense. Normally i don't like that, it can be super annoying. But atm i really need some distraction from this selfish disgusting guy (MC Prime Vampire) so i just hope that the mc here is the "shy-dense" type with some cute romance, and not the "stupid-like-a-potato-dense" MC xD
Nattychris_22 Hey, thanks but i think that's nothing for me. As i said above, i really prefer harem settings with several interesting characters that all somehow end up together happily. So yea... additionally only 12 chapters and annoying kids are another thing i don't really like :x
Nebel Hey Nebel! It's quite a new story but maybe you can keep "My CEO Harem Cultivation System" on your future to read list? 
It's currently at six chapters right now but I have plans to keep it light and upbeat!
https://www.webnovel.com/book/my-ceo-harem-cultivation-system_18550691905102105
Girl here too. I’ve read Romantic Cultivator. The story is actually fluffy and fun if you are a girl. It isnt because the MC is dense. He just set his sight on a girl that he had a romantic relationship in the past (this isnt a spoiler cos u get to read this very soon) but he doesnt trust her when he had met her again because
....(this part u got to find out urself. Because there is a mystery here).
The MC is actually quite smart and caution if you reading from a neutral perspective. But although he tries to be smart but the heroines are smarter than him sometimes so he got outwitted by them. I think this part causes some male readers ego to be hurted because they cant stand smarter heroines. They may think they r smarter but i bet none is smart to solve the mystery.
Story actually has many plot twists, touching and fluffy movenents. It is a harem story that girls will enjoy 
Nebel
I am sure you will not be disappointed with Romantic Cultivator. MC is dense 5 Percent of the time and acts dense 15 Percent of the time, the rest of the time he's pretty smart. The story makes me smile and laugh most of the time. If you are worried about him being the passive type don't be.
Thanks for the feedback it is good and looking forward to more :)
Some of my suggestion might have been based on my current progress.. sorry.
Leporidere Nebel
Oh yeah, almost forgot about manga too. Well, since we are in a novel oriented site, but there are also some nice harem manga that we could recommend ;
"The World God Only Knows" a manga you should try to read it.
Another one perhaps the "classic" manga, Love Hina?
GegeSadewa
I don't think he would enjoy those two mangas. He specifically asked for a real harem where the MC accepts all the girls and neither of those two has a harem ending. "Love Hina" isn't even a harem, it's just a romcom and I also think that he wouldn't enjoy the girls constantly beating up the male lead for no reason. As for "The World God Only Knows" I also wouldn't recommend that one because the majority of the heroines always forget about the MC which makes all the romantic development between the MC and them pointless. It also doesn't help that the majority of the heroines are never mentioned again after they are "conquered".
Nebel
I actually have a few more mangas to recommend if you want. You can also try Umi no Misaki and Kekkon Yubiwa Monogatari, those two are also good in my opinion. Also if you want me to recommend you novels I could recommend you highschool dxd and mushouku tensei if you haven already read them. You can download the volumes on jnovels and read them.
Leporidere Haha, I guess I also already forgot what the op ask for. So it must be harem end, and its a fluffy happy harem, not sad or tragic.
Hmmm, kinda difficult since its also some ideal criteria of harem that I would also love it. If we could found it. Especially the harem end since some of our suggestion is not ended yet, or already end but not the end that we hope for.
- Edited
I'm just going to clarify somethings that you might have misunderstood, Illicit relationships definitely start out R-18 heavy, but for a new author who doesn't exactly have their own style yet they can tend to focus too much on one aspect in the beginning, you have to give them time to find their groove(almost everyone is clumsy at first when they try something for the first time), the plot eventually starts moving forward so just wait for it. In terms of incest with the mother, you probably realize this but he was a young man who transmigrated into the body of another young man, even if she is the new bodies mother biologically for him she can also be considered a beautiful older woman, even though he got the bodies previous owner's memories there is still some disconnect between his mind and body. When it comes to Prime Vampire I didn't really get too far, but a decent portion of the girls where I got had known the MC before, while what you say may be the case it is also a fact that there are girls who knew him prior to the beginning of the series and the author plans to write something to address all these concerns(he had something before but it wasn't exactly what most people are looking for), so again give him some time and some relationships you consider forced might make sense.
For my recommendation, prime originator somewhat fits what you want, relationships start out forced but again that is a new author not knowing what he is doing, the girls added after are done well, even then those previous girls get some development later on. I want to say there is no separation but it is one of those things where it depends on the person in question. Sometimes the MC will leave the women behind but it isn't like he is abandoning them, he remains on the same world but an example is he basically goes on an underground exploration looking for resources and shit right under his family while they stay back home with their families to cultivate in safety(also it isn't like they're just staying home using his hard-earned resources, instead he actually wants to go on these dangerous explorations, they hate that him leaving and taking these risks but he needs to do it to grow stronger and they respect his wishes and trust in his abilities).
Another recommendation is The way of the Dao.
Hey,
Again: Thanks a lot for all this input. I'll try to respond to everything here, if i forgot something, please let me know :x
RachelRuth maybe, as you said yourself, it hasn't many chapters jet to say anything. I'll try to remember it and if its progressed a little i may give it a try. IF the genre is fitting then.
Fanjo Thanks! After your explanation i started to read Romantic Cultivator two days ago. I am around chapter 58 now and i totally agree with your opinion. I was slightly annoyed by the "forced drama" of him not telling the girls who he is because of his stupid beard. BUT i was really happy that every woman figured out who he was. Overall i really like that all the girls are smarter/stronger as him, but at the same time he isn't totally useless/dump either. For the future i just hope for little more fluff and more time together (together with the girls, because atm he goes from place to place, always "finding" a new woman, but the other girls are left behind).
Really looking forward to it tho =D
SecretWolf as i said above, yeah i really enjoy Romantic Cultivator xD thanks. And regarding the other novels, don'T worry. I just have some problems when girls are treated badly. I KINDA can deal with it if they aren't really well developed because if i couldn't i'd have even less to read, but if they just feel like "pleasure dolls" and treaded badly i get really pissed and can't read stuff like that at all.
GegeSadewa Leporidere BoobLover is mostly right, i highly prefer harem setting because i just like the "family" side of it and everyone being able to stay together happily.
Regarding Manga general; So far i haven't read any mangas since i always preferred flow text. If you have any long and fitting mangas i'm really happy about any recommendations. But it would be great if you could give me some key marks what the manga is about and what i can expect xD
Regarding Highschool DxD... i am not such a big fan of the mc... super pervert but at the same time also super dense and not really accepting any romantic approaches at all... supper annoying japanese archetype. And I already know Mushouku Tensei
FunnyBuns Regarding the first part: Let me split Illicit and Prime Vampire in two different parts.
Illicit: I was told to read past chapter 30 and i actually even did read into chapter 50 or so because at that time i had nothing else to read. Overall i understood the Idea of the novel and even the romance was... "ok". It wasn't only sex, he cared for the girls at least to some degree and the girls had different personality's. The only thing that was just "bad" (personal opinion) was, that the incest relationship wasn't questioned at all. I get why he wouldn't mind. But at least his mother and aunt would have some thoughts of it. I don't say that they should come to the result that its bad and stop it. But there should be some explanation about how they think, why they're doing it or ANYTHING like that.
But overall at the end i dropped the story because it just wasn't my cup. The only thing i thought was cute was, that his mother and aunt care so much about each other. That was fluffy. Beside that it was just to much "fuck boy" attitude and "capturing/wooing girls".
Regarding Prime Vampire: First and foremost: I was really disgusted by how the mc treated girls only for his pleasure. He was ruthless and treated them just terrible, wanting to just fuck them as soon as possible and as rough as possible while all of them never had sex before... Thats just a disgusting character that i really dislike.
BESIDE that, the novel had several other big problems. But as you said, new author and they all can improve. I actually wrote quite a long and detailed review after the last chapter i've read. And i didn't put it in the official review section, because i didn't want to give a very negative rating. I just wanted to point out my personal opinion and actually had a short chat with the author.
But i'm quite sure i will never pick up that novel again. I was really disgusted by the mc. Treating girls like that, only caring about his own pleasure... i have a hard time dealing with this attitude... i require more fluff ;)
So in short: I can deal with a rough start and lagging development of characters early on. But if the mc only cares about himself and treating girls badly and/or using them only for sex, i don't want the girl end up with him (because i personally can't imagine that they will find happiness with him) and then its pointless to continue reading.
Regarding your recommendations: After what i said above, what kind of rough start has Prime Originator?
What you said about separation; Separation for me is more like "lost contact for many yeas, not sure if ever see again" thing. Its ok as backstory, but if its occurring in the novel itself, i dislike it a lot. I prefer if the "group" stays together and spend time with each other, but its fine if he leaves sometimes to do "stuff" AS LONG as the other girls don't fade away (those harems were new girls join every minute and at the same time most of the "old" girls are never mentioned again really suck).
Nebel You see that is why I said it depends on the person when it comes to separation, yeah he goes out an explores the world but he returns home to them, some people might consider leaving them behind while the MC goes of exploring as Separation but it never lasts to long, the first time he went off was like a week or two and now he might be gone for a few months to a few years as he has to infiltrate a certain place to save his mother so he has to gain these people's trust which could take a while.
The forced relationships at the start was like some girls pretty easily falling in love, though he intends to marry these women when things calm down(things are way to hectic to get married at this point), so even though it starts out pretty rushed it is developed later on. Girls added later on are more natural and the relationship is built over time.
I can understand why you wouldn't like prime vampire, though as I said I didn't get too far as I decided to wait for the author to add backstory. I can also understand you feeling little romance in illicit relationship at first but it does get better over time, I won't try to convince you further but just understand you seem to have stopped too early to see the improvements.
Nebel Sorry had some stuff to do but if you want to have an idea of what illicit relationship becomes later on try chapters 196 and 197, even if you have to pirate it I feel they will convince you it is worth your time and money. I couldn't find other chapters unfortunately as that would require me to go more in-depth looking for them so I went with one that was obvious by the title.