Two coworkers agree to become sleep partners, but then feelings start to develop. (Main story)
Chapter 5 - A man's unrequited love for his best friend, who is getting married.
Good news about chapter 5 - it has its own manga with a happy ending and new love! Plus the friend has a cameo and is a super great guy.
Two men who have been dating a few months finally have sex.
Sofure Buka!