amit34521 uh dunno, i could only think of it as onion girl (its very likely her, you know that in some chapter she shrink right? and character illustration from the novel sometimes differ with the manhua).
maybe i'm wrong, its probably duoduo or dragon/fish girl (very very unlikely though). or maybe the spirit girl? i doubt that. but who knows...
though i'm sure its definitely not the old dude yellow mountain.