Throughout her relationship, Xia Mo repeatedly feels unappreciated. After accumulating a heart full of disappointment, she decides to let go before it's too late. She embraces another sincere connection and begins a new life of her own. Only belatedly does her ex-boyfriend realize the value of what he has lost and turn back, hoping to make amends and win her back. But when he finally rushes to find her, he discovers that he doesn't even know one of his girlfriend's most basic little habits. This regret is one he will never get the chance to make up for.