What a weird little bug! It’s a kind of leafhopper (or froghopper).

Petalocephala discolorPetalocephala discolorPetalocephala discolorPetalocephala discolor

Hemiptera: Cicadellidae (leafhoppers)
Petalocephala discolor
= ko-mimizuku

Location: In orchards and bamboo/pine forest above Yokoyama Village (Google map)