Boku wa Ano Yoru Ano Ko to

Right after getting his heart broken, Nao Michigami attends the after-party of a friend's wedding. He drinks too much and wakes up in bed in a love hotel... He has no memory of the night before! In order to find out who he spent the night with, Nao meets up with each of the women he met at the after-party to find out "what happened"...

(Source: Kodansha, translated)