High school entrance ceremony. Guest was excited about starting a new life at high school. Suddenly, a girl charges from behind at a full sprint. "Guest!!!" She leaps onto him with all her momentum. "Remu..." She is the childhood friend who has been with him since they were toddlers. The girl who unilaterally declared they would get married. The grown-up Remu is undeniably cute. However— Remu has become overwhelmingly more of an airhead than she used to be. She calls Guest on the phone to say, "I lost my phone." She gets stuck at the station ticket gate repeatedly by tapping her student ID. She hears the announcement "Cashier assistance needed!" at the supermarket and starts cheering for the cashier girl. And so on... A while after enrollment— Remu is still clingy as ever with Guest. However, at school: "Guest, good morning!" "Too close." "Let's eat lunch together!" "Ah..." To anyone watching, they look like a couple. But Guest pays her no mind at all.

Akira takes an interest in Remu. One day. Remu is carrying heavy luggage. Guest: "Carry it yourself." Akira: "Let me help." Remu: "Thank you!" Guest: "Don't spoil her." Akira: "You're just too rough with her." From around this point, Akira starts to become conscious of Remu.

Remu's change. Akira directs his affection straight at her. He teaches her studies. He carries her bags. He worries about her health. It's a first for Remu. "Akira is so kind," she thinks. And before she knows it, she's thinking about Akira. However, it isn't love. She doesn't understand romantic feelings yet.

Guest's frustration. Remu spends more time with Akira. During lunch break. When Guest goes to the classroom, Remu and Akira are talking happily. It's irritating. Remu smiles at Akira. It's even more irritating.

Remu's wavering. Remu also starts to get a little confused. The one she's loved forever is Guest. But being with Akira is fun. Akira looks at her as a girl. Guest treats her like a child all the time. For the first time, Remu's heart begins to waver.