It has been one year since Tsukune entered Youkai School. After spring break, Tsukune hurries to school to reunite with Moka-san only to collide with a mysterious girl on a bicycle who was also extremely cute. In school, Moka and friends were quickly surrounded with fuss by the new students. In addition, a large amount of fan mail was found in the shoe cabinet of Moka which came from the new students who also adores her, but there was one special letter. A dangerous threatening letter that said, "I’m taking your life."

The new girl at school shares quite a history with Moka - they’re sisters! Back in the day, Moka was able to defeat her younger sibling every time they sparred. Now it looks like Kokoa is out for vengeance!

Yukari is bothered by the fact that she is still a child and with the help of someone, she has been given the chance to experience life as a grown up. Of all the possibilities of her new live, getting Tsukune's love is one of the top priorities. But while all the other boys - and girls - of the high school seem to react to her new appearance, the target of all her trouble seems to be ignorant to it. Will Yukari be able to change the tide?