Karakawanaide, Hatori-kun.

Tooru Orikasa is a shy college student and a closeted fudanshi. He has been quietly going through university life, but somehow, he catches the attention of Ao Hatori, a bright and outgoing student from another department. Thanks to Hatori's easygoing and thoughtful nature, Tooru finds himself going shopping and even to karaoke after class. Spending time with friends is unbelievably fun!! Then one day, after witnessing two male friends kissing, Tooru is left flustered. That is when Hatori leans in close and asks, "Want to try it?"—!?

(Source: Futabasha, translated)

Note: Includes one extra chapter.