Mayoi Neko Overrun! is a Japanese light novel series written by Tomohiro Matsu, which was later adapted into an anime series in 2010. The story follows Takumi Tsuzuki, a high school student who helps run a bakery with his adoptive sister Otome. Their lives take an unexpected turn with the arrival of Fumino Serizawa and other unique characters, leading to comedic and heartwarming adventures. The series explores themes of friendship, family, and the challenges of adolescence.