Boiling Frog Syndrome

Jeh Yillo has a highly specific, twisted fetish: he's obsessed with guys who have terrible personalities and wear glasses. Enter Gwak Changhyeok, the school's most hated grade-level head teacher. When Yillo accidentally witnesses the notoriously toxic teacher speaking softly to his girlfriend, his obsession ignites. He decides to reel him in like a frog in a pot, heating the water so slowly Changhyeok won't even realize he's being boiled alive...until Yillo has the opportunity to devour him whole.

(Source: Lezhin Entertainment)