As a regular high school student in Japan, Yuuken “Yuu” Enma is practicing for a kendo event. But he got hit by a black carriage just the night before the match. When he wakes up, he finds himself in a famous magical school of Twisted Wonderland, The Night Raven College. This place welcomes only students with magic powers, but Yuu has no magic, and no one knows why he is here.
Yuu wants to go back to his country, but this is not an easy thing. His master helps him find a way, but Yuu is asked to do some tasks around the school. During this, he makes a mistake at the entrance ceremony, and the dorm leader of Heartslabyul, Riddle Rosehearts, starts taking him as trouble.
Yuu makes two friends from first-year students, Ace Trappola and Deuce Spade. But they both got expelled from school for damaging the school property. To cover the things, they are asked to repair the building, and Yuu joins them. But Riddle, who is also known as Crimson Tyrant, is hard to please and has strict rules.
