Yusei Matsui was born on the last day of January in Saitama Prefecture, Japan. He has been drawing manga since elementary school. Some of his favorite manga series are Bobobo-bo Bo-bobo, JoJo's Bizarre Adventure, and Ultimate Muscle. Matsui learned his trade working as an assistant to manga artist Yoshio Sawai, creator of Bobobo-bo Bo-bobo. In 2005, Matsui debuted his original manga Neuro: Supernatural Detective in Weekly Shonen Jump. In 2007, Neuro was adapted into an anime. In 2012, Assassination Classroom began serialization in Weekly Shonen Jump.