Koicaros's Things

I don’t remember the name or character names but the plot was that there was this program for couples and they get a scholarship into a college and so the main characters decide to fake get together, but there’s a quota they have to make to prove they’re together by having sex. I remember the top having brown hair and the bottom having black hair and I think the bottom was trying to jump off a bridge when the top finds the bottom and decides to help but later it’s revealed that the top has know the bottom for a while and was stalking him a bit after seeing a picture of the bottom.