Responses
Sumi didn't know Utou loved him back until after the bite mark, Utou was the one who knew and didn't say nor do anything until it was late
Shiratori hates Utou and made all of this for hurt him using Sumi.
read chapter 11 here https://www.facebook.com/pg/TinyBLLover/photos/?tab=album&album_id=1348154565355697&ref=page_internal
After he went and got a pair when he totally knew their love was mutual just got to me. Like he got what's coming to him I just feel bad about the other guy having to go through it. (I'm sorry I forgot names)