Saigo no Door wo Shimero! Summary:
From DMP: What would you do if your crush of many years suddenly got married?! After attending his beloved Saitoh's wedding, broken-hearted Nagai gets a little too drunk for his own good and lands himself in a hotel room with the bride's guest, Honda. To top things off, just when he thought he was getting over things he finds out that newlywed Saitoh's bride has run away. What will become of this developing love-triangle?