Kaya-chan is infamous at kindergarten for being a troublemaker. But Ms. Chie, who's been assigned to look after her, soon discovers Kaya's hidden abilities. Get ready for the ultimate horror-action adventure set in kindergarten!

Welcome to the fascinating world of Gensokyo, in which youkai (A term for all sorts of spiritual creatures), animals and some humans live, completely separated from our world by a magical barrier. The only gateway between the two worlds is the Hakurei shrine. Reimu Hakurei is the maiden working at said shrine. Whenever problems of supernatural causes (known as "Incidents") occur, Reimu goes out with her friends to investigate, eliminate the cause and hopefully restore Gensokyo to its equilibrium.

The entire universe is divided into the inner universe and the outer universe. The two universes are enemies of each other. The outer universe is ruled by demons, and the inner universe is divided into The Realm of gods, the Eternal Realm, and the Mortal Realm. In the universe, there are countless mortal worlds like the Tianfa Continent, and they are collectively referred to as the Jiutian Xin Region. In the field of Jiutian Xin, nine immortal emperors commanded all star fields in nine layers. Above the nine heavens is the realm of purification of immortal gods.

Insults aimed at Saku Chitose are a dime a dozen. Nicknamed "Class 5's womanizing scumbag," he is constantly slandered online by those jealous of his popularity. Luckily, that barely makes a dent in Saku's confidence. Outside niche internet forums, he is the reputable figure his schoolmates admire and a model student his teachers trust. As his second year of high school commences, Saku reunites with his old friends and befriends new ones, all belonging to the school's social elite. However, the fun is cut short when Saku's homeroom teacher instructs him to convince his shut-in classmate, Kenta Yamazaki, to return to school. Wishing to wrap things up quickly, Saku visits Kenta's house the very next day. But the task proves more challenging than he expected when he discovers that Kenta is firmly and fully on the Saku hate train. If he wants to preserve his impeccable image, Saku must find a way to win over Kenta and bring him back to school.