Taro Arai

Taro Arai (新井太郎 Arai Tarō) is a student in Yamaku who is only ever seen sleeping in Hisao's homeroom class. That and his drool give the impression that his is not that bright.

Taro has monoplegia -- a paralysis of a single limb, usually caused by cerebral palsy.

Etymology

The name Taro means "thick, big" (太) (ta) and "son" (郎) (ro).
Taro's surname Arai means "fresh, new" (新) (ara) and "well, mine shaft, pit" (井) (i).