"The 'Secret' Tape"

Sero Hanta has been working on a secret project. One he's poured his heart into for Kyoka Jirou; it's his way of expressing feelings he's too afraid to speak aloud. One night after finishing a group project with his classmates Momo, Denki, Ochako, and Sato, Sero finds himself alone in the common room in their dormitories late at night. He's lost in thought about this secret demo but, when Jirou accidentally finds him there- she asks why he's up working still so late.

Caught between his feelings and the fear of rejection, Sero struggles to decide whether to share the song he's written for her. As their late-night conversation unfolds, he learns that the hardest part of writing music isn't creating it- it's the courage to share what it truly means. Will he leave Jirou in on his secret, or will his song stay hidden in the shadows?

Plenty of headcanons here:

Sero is Hispanic.

Jirou has adhd and autism, especially selective mutism. Her classmates are aware of this and sometimes sing to her when she's not feeling verbal.

this is also published on ao3, same username.