Kenichi Mitsuba  

, 三葉 ケン一

A 10-year-old boy attends middle school but struggles academically. Despite this, he harbors feelings for Yumeko and is pursued by Kemumaki. The boy often manipulates Hattori to assist him in various situations, even during extreme circumstances (such as seeking training to become a skilled ninja). He frequently disregards his mother's instructions, resulting in severe reprimands. Despite his academic shortcomings, he exhibits a strong habit of helping others. Kemumaki consistently subjects the boy to mischievous schemes.