When something (most often Japanese Media) is so messed up and/or disturbing that you can say with confidence that "only a Japanese person could think of something that gnarly"
The Anime, School Days, (and especially its ending) is the epitome of Japanese Gnar.

Otaku 1: This anime is crazy! This chick had a miscarriage and went insane! She ate the dead fetus and merges conciousnesses with it and then she starts murdering a class full of elementary school students because she is jealous that other parents children actually survived! It's great! In the end an 8 year old kid cut open her stomach and removed the fetus, which then became a massive blob of evil that devoured the mother, and then corrupts the 8 year old kid, driving them insane.
Otaku 2: dude... that is some next level Japanese Gnar shit. You're making it sound like a masterpiece, it's just a bunch of sick perverted trash.
by Ravenous Rena November 20, 2017
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