After losing his mother young, an adult son was raised alone by his father until Honami became his new stepmother. She is kind but absentminded and often wears revealing clothes, making it hard for him to treat her purely as family. During a scorching summer, he sees her sleeping with beads of sweat covering her skin, and his forbidden desire grows until he can no longer see her only as his mother, leading to a sweaty life together filled with creampies.