Baek Yeon-ha finally escapes her workaholic lifestyle upon retirement. Despite regular exercise and leisurely rest, she suffers from insomnia every night. The only one who can help her sleep is Joo Seong-bin, her next-door neighbor who's 6 years younger, whom she's known since childhood. However, this guy who used to be just a kid... "Noona, I like you." Confesses his feelings... "Noona, I'm on your mind, aren't I?" When did he stop being just a close younger brother figure and start feeling like a man? A heartwarming romance about a devoted younger man who soothes the sleepless Yeon-ha's wounds. "Starting today, I'll help you. I'll help you fall asleep."