All roles are performed by adults. With her husband away on a long business trip, Ryo works out to burn off her pent-up sexual desire. When her adult son’s friend Kosuke visits one day, she glimpses his young, thick cock and cannot look away. Unable to restrain herself, she makes a move on him. Ryo initially delights in being made to cum again and again, but Kosuke’s stamina cannot be satisfied after only one or two rounds. His relentless pounding goes on without end, and as the daily orgasms continue, her body eventually begins crying out from the strain.