The main character, Kannin Manten (nicknamed "Kannin"), a 6th grade boy who attends Hanamaru Elementary School, is an honor student who keeps getting perfect scores in tests. However, the reality is that he continued to get perfect scores on all cheats, and he used cheat tools called "Cheat Goods" and the help of his grandfather and partner, Grandpa Mac (real name "Mantenmaku Kintaro"). Use it to fight against various fierce people such as tests, quiz competitions, teachers and groups trying to find out cheating. Yui Uenomori, the heroine whom Kannin has feelings for, Sub (real name "Saburo Ichino"), who claims to be Kannin's number one disciple, Kannin's homeroom teacher, Kinpure Kaneuchi, and Kannin's rival. We will also deepen our relationship with people such as Raiba Ryu, who calls himself.