A son named Ataru who can't hide his excitement every day with his father's remarried partner. His stepmother is a young and cute Chisa with an H-cup. Her body was so lewd that it made him unsure of where to look. His father's work is busy, and there are often days when he can't come home, so the frustrated Chisa would always comfort herself in the bath. However, knowing this, Ataru couldn't just watch anymore, and one night, he sneaked up to where Chisa was sleeping…
