Boku no Kanojo wa Boku no Koto ga Suki ja Nai

Synopsis

My girlfriend Chisa is in love with another man. I won't do anything she doesn't want to, and I won't lay a finger on her. Simply because she has someone she likes who isn't me. However, I know that one day, she will show to me the same face she shows to the one she likes, and I'll continue being her boyfriend today once more. (Source: Ichijinsha, translated)