Twenty-three-year-old Lee Ga-eul, who gave up on dating and devoted her life to finding a job. Before she graduated from college, she just wanted to have sex, so she found a like-minded person and took the plunge to have a one-night stand with her. And after a while, she comes face to face with her one-night stand in a place she never expected to meet. “So, how old are you?” “… … “Two.” "what?" “Twenty-three years old.” "twenty three?" When she looked up at the sound of laughter coming from above her head, a man with a shiny appearance that did not match the old apartment was standing with his forehead pressed together. “So how old are you?” A one-night stand that should have ended as a one-night stand. He was her boss, whom her brother cursed at every day. “… … Thirty-three.” “… … yes?" “He’s ten years older than you.” That's ten years older than Gaeul.