Hello there a rookie novelist is entering the contest, system genre is the best no questions needed!
My novel is called Soul Eater Sovereign, the main character get spirited away and eventually wakes up inside a child's body named Stigma. Taking in the child's identity, he eventually learns that he has system called Soul Eating System a system that relates to soul manipulation. Though Heavenly Beings or immortal beings will appear sometime in the story, since his system has the power to upset the natural balance, in other worlds killing immortal beings if he wanted too.
The main character has three main skill: 'Essence Reader', 'Soul Eater', and 'Poltergeist'. Essence Reader, is what pears through the soul telling the caster the secrets of the decease. Soul Eater, is based on the demon Soul Eater that devour soul that is said to contain pure energy. Poltergeist is a skill where he summons servants that take the form of black mass that responds to his every command.
Eventually he finds out, that he had gained a demon who takes the form of a small imp, that acts as the mentor and a constant reminder that his anxiety and anger are more than he can ignore. As his adventure continues, he will gain comrades subordinates and love interest.
The system is referenced like those in old rpg games, if you want to understand the reference.
Here is the link: https://www.webnovel.com/book/11417711806358205/Soul-Eating-Sovereign