1. Slipping into the futon, thoroughly enjoying the sensation over the clothes, and then carefully peeling off each layer of clothing.
2. Slowly and gently, savor the female body with your tongue and penis, making sure not to wake her.
3. Insert slowly while she is still asleep. The woman will soon wake up in surprise but will likely soon accept the man.
Revive in modern times, the "yobai" deserves a fresh look.