Yamai Mitsuri
A classmate of Komi and Tadano who's basically obsessed with Komi. Her name is a play on "yandere" mixed with "yamu" (meaning to suffer), which pretty much sums up her whole deal.
Yamai worships Komi like she's a literal goddess, and she can't stand that Tadano gets to be close to her. She's constantly crossing boundaries with Komi in increasingly uncomfortable ways—sexual harassment is basically her default mode. The yandere tendencies are real: she swings between devotion and possessive jealousy depending on the moment, and Tadano usually bears the brunt of her resentment for daring to exist in Komi's orbit.
Content compiled by AnimeList.moe from publicly available sources.