Haruka Takayama and Yuu Sonoda are two best friends who are just starting high school together. However, as the school year starts and the two starting making new friends, Haruka worries that her friendship with Yuu will stop being special. After Yuu suggests that the two of them do something that is unique to them, Haruka suggests they start kissing each other in secret as proof of their special friendship. Later, Haruka and Yuu get locked inside an empty classroom whilst they were kissing on the veranda, requiring them to cross a large gap between verandas to get to the neighbouring classroom.
高校入学を明日に控えた高山春香は、親友の園田優と同じクラスになり期待に胸を膨らませていた。 クラスには優の他にもコトネやしずく、楓やゆずら個性的な女の子がいっぱい。しかし仲良くなれそうなクラスメイトがいることに安堵すると同時に、 すぐ友達ができる優を見て春香は少し嫉妬してしまう。空き教室で一人そんな物思いにふける春香の前に優が現れ、「私たちは、他の娘とは絶対しないことをしようよ」と提案し…。
단짝인 유우와 함께 미나토 서부 고등학교에 진학하게 된 하루카. 다행히 같은 반이 된 두 사람이었지만 하루카의 기대와는 달리 두 사람의 책상은 멀기만 했는데...
