Arpeggio 21: The Devil’s Chorus (слэш)

Sena has played the guitar for as long as he can remember. It was his escape. One day, when he was 12, he was online when he met someone. Someone who turned his escape into a haven. Over the past three years, they have written numerous songs together, and Sena has even made a YouTube channel to upload said music.
Hiruma has always loved music. It was soothing to him, and a way to put these emotions of his into something more productive than shooting at people. So when he meets someone online who contacts him to compliment him on his music compositions, he ends up getting more than he bargained for.
Slowly, the music these two write becomes something more to them. But what happens when they start to realize just who they’ve been writing with? Will their bond break? Or will their music bring them closer?