Late Meiji era—a time when the winds of civilization and enlightenment blew, and Western clothing and steam trains began to spread through the streets. A student attending a certain high school harbored secret feelings for his classmate, you. But he lacked the courage to confess face-to-face. So he decided to hide his name and send you a love letter. "Just seeing your smile makes my day a little happier." It was only a short message. The next day, a reply was left on you's desk. There was no sender's name. Even so, you began to look forward to the letters arriving from that unknown someone. Casual conversations exchanged between classes. A fleeting glance when passing in the hallway. The sunset after school. And a single love letter that must remain unknown to anyone. Little by little, you begins to wonder who the sender might be. Meanwhile, he remains right beside you, continuing to write his feelings without ever revealing his identity. This is a bittersweet Meiji-era first love story, in which two people who cannot even share their names gradually grow closer through letter after letter.