Saigo no Door wo Shimero!

Fuente: AniList

After being best man at his best friend's (Saitou Toshihisa) wedding, Nagai Atsushi realizes that he might have fallen for him. Nagai, drowning in his sorrows and hatred for the new bride then meets Honda Kenzou, another guest at the wedding. Honda takes care of Nagai when he was dead drunk and now Nagai can't stop thinking of both Honda and Saitou.