Kabutomoaki (カブトモアキ) is a member of Dropout Sensei and acts as the band's bassist. He also writes the songs for the band.
He joined the band at the insistence of his childhood friend, Kuwagatatsuya, although he really enjoys music anyways. Kabutomoaki teases and argues with Kuwagatatsuya a lot, but he still considers him a close friend.
He's considered a calmer person in comparison to his childhood friend, but Kabutomoaki is still capable of getting really heated sometimes.
To his classmates, he's known as the gloomy guy, but, despite that, he's rumored to be popular with girls, although he's simply not interested. He enjoys reading books under trees and also loves watermelon. He also apparently has great luck, as shown in him winning the mall's lottery or drawing fortune slips that promise him great luck for the next three years