So many perverts work on mainstream Anime... Now one of them will leave the mainstream just to focus on pornographic Anime... : https://animegalaxyofficial.com/one-piece-animator-create-hentai/
Here is all the Anime he worked in : https://www.animenewsnetwork.com/encyclopedia/people.php?id=27704
He worked on some series I liked like Card Captor Sakura and InuYasha... And now he works on Anime porn...