Kyoushitsu no Katasumi de Seishun ga Hajimaru

Mari Yoshida, a girl that only becomes the main character for a brief moment, before situations go sideways and she becomes cringe. Meanwhile, the alien Nell has held a dream of wanting to do something on Earth. Also in the classroom are people wanting to hide their otakudom, people who act out their ideal life on social media, and people who have confidence in their special destiny. Every kid in the classroom has their own secret, and you can't even claim to understand the kid right next to you.

(Source: Kadokawa, translated)