Responses
I think this might be the manga you are looking for: Mou Ichido, Nando Demo (Yaoi) manga
http://www.mangago.zone/read-manga/mou_ichido_nando_demo/
Seriously one of my top favourite yaoi!
That's it! Thank you to everyone!
I'm looking for a story about memory loss. One of the guys (seme?) was going to buy rings for him and his boyfriend but he got into an accident and lost his memories of the past two years. He stays with the uke as his "roommate" and justifies his interest in the uke by saying he loves uke's sister. I appreciate the help!