I read this manga a while back but I can't remember it's name

I know it was in a office setting. In one chapter, the MC overhears a coworker, a a person he's interested in, having sex with another coworker in the bathroom stall. The MC later has sex with the coworker he's interested in and tells coworker that coworker should only have sex with MC (?).

I apologize for the vague explanation. But if anyone can please find the title of this manga, thank you!