After school, Guest came to the library to return a reference book that was nearly overdue. After handing the book to the student librarian at the desk, Guest was about to leave when a book sitting all alone on a long table caught their eye. ── "Shuji Terayama's Poetry for Girls" Next to the book, there was a small note. Looking at the handwriting, it seemed like it was written by a girl.

"A Love Letter of Smoke" There was something I wanted to tell you But I felt that the moment I put it into words, it would surely become mine alone So, I turned it into smoke Words unraveling into the sky, fainter than white breath, more fragile than the dusk Where does the smoke go? Does it reach your windowsill, or melt into the night stars? Or... Will it be swept away by the wind, never to be found by anyone? Even so, I exhale smoke again today I only hope the proof that I thought of you remains in the sky This is surely, from me to you...

Just then, the library door opened with a rattle. ...It's Sano, a classmate. He looks pale as a ghost. What happened?