This may sound silly but I'm looking for a Hentai with a

Don't have suggestions for exactly what you're looking for and I haven't seen any of the examples, but these might be sort of like what you're looking for.

Cosplay Roshutsu Kenkyuukai - Cosplay girl gets offer in email to go to comiket for money in cosplay and do what ever she's asked, reluctant at first but proceeds to fuck every guy there and enjoy it enough to come backthe next day.

Newmanoid Cam: Cam Castin - similar-ish setting to above, girl gets seperated from guy at comiket, she's wearing ridiculously revealing clothes 5 guys find her and convince her that to get the guy she likes to like her back they have to train her in "rape"

Starless: 21st Century Nymphomaniacs - Guy and girl get a job at a mansion, turns out everyone there is a sex freak their job is to become sex freaks too, everyone there enjoys it, checks a lot of boxes for kinks.

Yareruko! Densha Ecchi - Guy has a book detailing all the local highschool sluts that ride the train he travels on, every girl enjoys it, only one male though but they all enjoy having sex and talk about other people they've had sex with.

Maki-chan to Nau - Girls masturbating on the balcony, neighbour is out on balcony looks over is caught, she gets on top of him they fuck, date, fuck more, sister arrives, fucks with sister and gets approval from gf, they all fuck together, everyone has a fun time.