Sayo-kun no Omajinai

About

When he was in elementary school, Suzue Masato met Tsutsui Sayo, who was in the next class, at a psychiatric clinic. Sayo asks Masato to be his friend. They promise to stay friends forever, and so the two become best friends. However, after becoming a junior high school student, Sayo becomes addicted to online streaming and starts to get estranged from Masato. Feeling betrayed, Masato started hating Sayo and posting hateful comments on anonymous message boards, but...

A short BL visual novel.

Source: IGDB