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

However, by the time they reached 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 remained intensely possessive and controlling, becoming an abusive girlfriend who did as she pleased while denying Guest any freedom. Even so, Guest believed in her, waiting through their first and second years of high school, hoping her love would return and she would become the kind person she once was.

Finally, 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 dozing driver ignored a red light and hurtled toward them. Guest moved instinctively—Kanade was still precious to them. Guest pushed Kanade out of the way and was struck, narrowly surviving the accident.

Seeing Guest sacrifice themselves, Kanade realized for the first time that she might lose them forever. She resolved to love Guest once more and start their relationship over.