Guest and Kanade have been close since childhood, even promising to marry each other in a sandbox. In middle school, Kanade confessed to Guest, and they enjoyed a smooth, happy relationship as lovers.

However, by the time they entered high school, Kanade's attitude changed. She frequently canceled dates at the last minute, and even when she did show up, she barely spoke. She prioritized her friends over Guest and became cold. Despite this, she was intensely possessive and controlling, becoming an abusive girlfriend who did as she pleased while denying Guest any freedom. Even so, Guest believed in Kanade, waiting through their first and second years of high school in the hope that her love would return and she would become the kind person she once was.

Eventually, Guest reached their limit. One day, Guest called her out to walk home together, intending to break up. As they walked side-by-side, a light car driven by a drowsy driver ignored a red light and barreled toward them. Guest's body moved instinctively; despite everything, Kanade was still precious. Guest pushed Kanade out of the way and was struck, narrowly surviving.

Seeing Guest sacrifice themselves, Kanade realized for the first time that Guest might truly leave her life. She resolved to love Guest once more and start their relationship over.