A single father struggling to make his comeback as a screenwriter falls in love with one of his students. Meanwhile his son, studying to become a chef, falls in love with his teacher. Love is great for creativity, but it comes with a price.

Yeong-jae (Sin Joo-ah), Ha-eun (Koo Ji-sung) and Chun-hee (Yoon Chae-i) have been friends for 15 years since high school. Yeon-jae is the youngest of a fine hotel owner and she aims to sleep with 1203 men throughout her life. On the other hand, Chun-hee is an old-school minded high school teacher who has never had sex before in her thirty-something life. Wedding planner Ha-eun was in love with one man for 10 years but recently experienced the pain of losing both her man and work. Then one day, to celebrate their 10th year majority, they have a party of their own in room 1203 of Yeon-jae's hotel. They say the house breaks down if three girls get together.

The city hums with its usual noise and haste. Unable to keep pace with its restless speed, Se-yeon moves slowly, as if walking through a different time. Every day she brews her tea carefully, hangs her laundry, heads to work, and eats alone. She has a dream, yet never steps into it - only circles around it. Avoiding people's eyes, she goes to the darkened river after sunset and paints. It is the only moment she feels she is reaching toward her dream, the only moment she feels alive. There, in that night river, is someone else besides Se-yeon. By the same river, Jae-woo dreams as well - a dream of making a fortune by selling river sand. They share the same river, share meals, walk the same path, and spend a season together. At the end of summer, Se-yeon and Jae-woo finally come face to face with each other's fragile truths.