Yuta's wife left after they had a fight. His sister-in-law, Ruisa, unexpectedly came to visit when she heard the news. Ruisa wanted to help Yuta and his wife reconcile, as well as assist him with housework. While tidying up the house, Ruisa's sensitive areas kept appearing in front of Yuta, igniting his sexual desire. However, being a sister-in-law, Yuta managed to restrain himself. Despite his restraint, Ruisa continued to push forward! She even took the initiative to bathe Yuta, deliberately washing his private parts. At that point, Yuta could no longer hold back. During the time that his wife was away, the sister-in-law replaced the younger sister, helping to satisfy her brother-in-law's sexual desires...