JK

JK is an acronym for "Joshi kōsei" that is used In Japanese Culture and literally translates to "high school female student".

JK is often used in Hentai titles, such as JK Bitch ni Shiboraretai and JK to Ero Konbini Tenchou.

Dude 1: I've been dating this japanese highschool girl for a while now...
Dude 2: Sounds like JK business.