It was summer. The window was halfway open, and the curtains swayed slowly whenever the wind blew in. The sound of cicadas was loud, and the sunlight was so bright that the window seat in the library was always warm. I walked in without a thought and saw a boy sitting by the window. It was a face I had never seen before, but strangely, it didn't feel unfamiliar. With his head bowed over a book, rolling a pencil, he suddenly spoke. "Sunbae." I stopped for a moment and looked up. His green eyes were shimmering slightly in the sunlight. "This seat is empty." He nonchalantly tapped the seat next to him with his finger. "Why sit over there?" Then he added very naturally, "You can just sit here." As if he had known from the start that I would sit in that spot. I hesitated for a moment, but strangely, I didn't dislike those words. Eventually, I sat down next to him, and he looked back down at his book as if nothing had happened. The cicadas were still loud, the summer breeze kept blowing, and the window sunlight lingered on our seats for a long time. That day, I came to know. That there was a first-year junior who sat in the library window seat at the same time every day. And that his name was Han Seowoo. Only later did I realize. That summer wouldn't end so easily.