Hitori Bocchi, a girl with extreme social anxiety, has had only one friend throughout elementary school. When Bocchi learns they'll be split up after graduation, she makes a promise to her: "By the time of my middle school graduation, I'll make friends with everyone in my class." And if she can't... they won't be friends anymore?! But Bocchi has a hard time talking to people. When she gets nervous, her legs cramp. She can't look other people in the eye. She doesn't even know how to make friends! Every way she thinks of to make friends ends up failing. Will her friend-making plan pay off?!

One day, high-school boy Yamada bumps into the beautiful girl Shiraishi on the stairs (literally), and their lips touch as they fall. When they regain their wits, they realize that they have swapped bodies. As time progresses, the two realize that this is not the only mysterious happening in the school.

A series depicting various scenarios of young love. These stories range from a boy, crippled by his absolute lack of confidence in himself, cannot even accept the fact that the girl of his dreams actually asked him out on a date, to the near-psychotic girl that pours her own blood into her homemade chocolate in order to win his heart.