noun
university club focused on casual sex
Slang term blending やる (to have sex) and サークル (club). Refers to a university circle where the main purpose is socializing and sexual activity rather than a stated hobby or interest.
あのサークルはヤリサーだって噂だよ。
There's a rumor that club is a yarisā.
新入生はヤリサーに気をつけたほうがいい。
New students should be careful about yarisā.