Smut is kind of raunchy. Yaoi is for those interested in male-male love stories. Manga is just a wide range of comics from Japan that can be of any type. So, they're quite distinct from each other.
Smut fiction is a type of fictional writing that contains sexually explicit content. It often focuses on sexual encounters, relationships, and desires. However, it is considered a form of adult - oriented literature and may not be suitable for all audiences.
Well, a smut novel refers to a book where the focus is heavily on sexual themes and often has very detailed and graphic descriptions of sexual acts. It's not for everyone and is usually considered more adult-oriented.