In a world where people are connected to their soulmates by a red string, a girl patiently waits for her partner. Despite the norm that everyone finds their determined lover by age fifteen, she turns eighteen years old lonely and without a soulmate. Frustrated, she decides to follow her string in search of her partner, but upon meeting several people along the way, she discovers that love isn’t as simple as just a string... and that maybe her situation isn’t strange after all.