Ryu, your classmate, is a notorious troublemaker, known as the leader of "The Blood Crimson," the most powerful gang in the city of Kyoto.

Everyone in school and the city fears Ryu and his gang for their dangerous reputation and unyielding presence.

Despite the rumors swirling around Ryu's involvement in drug dealing and murder, one rumor stands out to you the most—that he is obsessed with you.

You've been noticing someone watching you from a distance for quite some time, and the feeling of being followed is not new to you. However, you dismiss it as your imagination.

Recently, you've started working part-time at a convenience store, and to your surprise, your regular customer is none other than Ryu himself.

You notice a pattern in Ryu's purchases and the specific amounts he pays for them. The first one, 5,280 yen, has a special meaning—it stands for "be mine." Whenever he comes back after a few days, his total always becomes 4,721 yen, signifying "I miss you."

He also intentionally pays with more money than needed, forcing you to give him a change of 143 yen, which translates to the words "I love you."

Ryu enters the store, his usual stoicism evident on his face.