Toru has spent most of his life avoiding crowds and trains, traumatized by a health incident from his school days. On his first day commuting to a job at a printing company that he finally managed to secure, he becomes ill on the train and nearly despairs. In that moment, he is rescued by a handsome university student named Hiiragi. Despite being strangers, Hiiragi acts strangely familiar and close to Toru, suddenly confessing, Please let me be your good luck charm. Toru soon discovers a curious side effect of this connection: whenever he holds Hiiragis hand, he becomes overwhelmingly and irresistibly sleepy.

The story follows Toru, who struggles with panic attacks that make everyday social activities like riding the train difficult, and Hiiragi, whose mysterious nature hides his own burdens. While Hiiragi repeatedly saves Toru from his anxiety-induced episodes, it is revealed that Toru’s smile and words saved Hiiragi in their childhood when he was troubled by his own special ability. Their bond deepens into a relationship where they become each others protective charms, allowing Toru to gradually experience the ordinary joys of life, such as eating out or traveling, that he had long given up on. The narrative arc includes moments of bittersweet misunderstanding but maintains an overall gentle, healing, and pure atmosphere.