Gundam Build Fighters

"Of course I'm going into Gundam Build Fighters!"

His vision blurred as he was suddenly placed into a white room.

"Sorry, I left out some things! We need to explain the enforcer part, you are indeed enforcing girls to have sex but the moment you enter a world there will be standard sex rules put into place for a sex enforcer. The girls only have sex with you unless you tell them otherwise, but if you want to change something about the world just say it out loud and I'll change it! Alright, CYA!"

Blacking out for real this time, John was plopped right in the middle of a futuristic Kyoto (I don't know where the whole thing takes place)