Leticia Dorman, daughter of a duke, is less than thrilled to be engaged to a crown prince. Betrothed since childhood and trained to be queen, she always hoped Prince Clarke would fall for someone else one day. So when he shows up at a ball with another woman, Lettie excitedly retreats to the countryside to start her new life—only for Clarke to appear, determined to win her heart.

After a long day, high schooler Shintaro Tokumitsu's plans for relaxing in his studio apartment take a turn when he discovers an angel on his balcony. The divine girl, Towa, reveals she's there to study humanity, and yet, despite his skepticism, he agrees to put her up. Prepare for the most heavenly and high jinks roommate experience of all time!