Renji was separated from his mother at a young age, and the days spent with his kind and beautiful mother were healing. One day, a letter from his mother arrived. After 20 years, the son's patience snapped as he embraced his mother. "I'm sorry. If Renji forgives me, Mom will do anything..." These words turned Renji's love for his mother into a dark desire. On a hot spring trip to reunite after 20 years, mother and son moaned in ecstasy as they fell into pleasure together.