Yayoi Kuribayashi (栗林 弥生, Kuribayashi Yayoi) is the brunette assistant of Mouse in the series.

An incredibly busty but skilled biology expert who also works as the school's nurse. She formerly worked at a pharmaceutics research lab where she was hired to an all-female staff considering her phobia of men. She’s Zach Kakio’s aunt but she always treated him like he’s her own son.