Sakamoto is a male black cat from the Nichijou franchise. He wears a red scarf with an embedded speech device made by Professor Shinonome, which allows Sakamoto (and other animals who wear the scarf) to talk to humans. He is aged 20 in cat years — older than both Shinonome Nano and the Professor — and speaks in a condescending tone towards them and tries to act like the adult of the house, though to his shame he occasionally succumbs to his cat-like habits.
His original name was Taisho (Boss) and was once Nakamura Kana's pet cat.
The artist kazenokaze uses this cat often in his works.