Class no Inkya Busu? ...Jitsu wa Chou Bijin Cosplayer Datta. Minna Shirazu ni Baka ni Shiteru kedo.

Synopsis

Akira Hazama, a high school boy, hides his otaku nature and enjoys his school life as a cheerful person. However, he secretly goes to a doujinshi convention and has a fateful encounter with a...? (Source: Kodansha, translated)