Potemayo is a mysterious creature that appeared one day in Sunao's refrigerator. The name Potemayo comes from first two characters of potato (ポテト, poteto) and mayonnaise (マヨネーズ, mayonēzu) — what Sunao was eating at the time. At first, she could not speak anything but the non-nonsensical phrase "honi", which she often utters even after learning how to say a few words like Sunao's name. Potemayo is very protective of Sunao; if anyone tries to get close to him, she will growl and attack the person until they back off. When taken around with Sunao, she rides around on his head. She has the personality of a young child around two or three years of age, but has a super deformed body, complete with cat ears on her head. Potemayo will fly into a jealous rage when Mikan tries to get close to Sunao. Potemayo is also telepathic, at least when others are thinking about her Sunao, and becomes violent when she "hears" Mikan even thinking about Sunao. A small chick named Tori (とり, Torr, lit. "bird") hangs around Potemayo and will often sit on her head.