Koi no Hanashi ga Shitai

From The Moon in a Box:
Before Minari knew he was gay, he convinced himself he was incapable of falling in love. Having spent the last five years settling for just sex with a friend from high school, he surprises himself by falling in love with and impetuously confessing to an acquaintance, Shinkawa. But will Minari's fragile ego be able to withstand the fear and uncertainty of a real love relationship?