It's not easy being a love-struck high school student. When Tsuyoshi Yamaguchi is walking to school one morning he notices underclassman Ai Minamizato fretting over a kitten stuck in a tree. Being the kind boy he is, Tsuyoshi saves the kitten, thus becoming Ai's knight in shining armor. She must quickly make a decision, though, when she finds out Tsuyoshi received an anonymous love letter. Ai's energetic friend Miyuki, who is ever the pleaser and not easily phased, devises a plan for Ai to steal some time alone with Tsuyoshi. If only one of them knew the letter was sent as a prank by Tsuyoshi's silly friend Minoru...
When they were young, Kazuki and her older sister Hatsune had Yuuji and his little sister Marie as next door neighbors; and while Kazuki developed a crush Yuuji, he and his family moved away for ten years, much to her dismay. Now, the duo is finally returning, and Kazuki eagerly awaits his arrival; she still has a crush on him, and wants to finally confess her love to the handsome and debonair man that Kazuki has become – or has he? Unfortunately for Kazuki, Yuuji has “evolved” into a typical teenage pervert who can’t keep his hands off her. Family isn’t much help, as Hatsune helps Yuuji at every chance she can get, while Marie and her air gun are ready to lay down the law at a moment’s notice. With hormones raging and hands groping, will Kazuki retain her feelings for Yuuji?