I like the idea, and it is nice to drift off with him inside but as everyone else says it slips out. I did once fall asleep on top of him after sex and woke up a bit later to feel him getting hard inside me, but can’t say whether he stayed inside or the angle was right once he started to grow bigger again.
It does slip out eventually, but as tired as I have been after sex, I can fall asleep before that happens.
I remember several times when we were sexually active we would nap in the afterglow all cuddled. Before long we would start to fool around again. I would get into her vagina while flaccid and after a few moments begin to grow and expand. She absolutely loved the feeling of my cock coming to life inside her vagina.
You've had it before. It felt so awesome to come alive not long after orgasm. To be able to catch a second wind is just fabulous. I can still do that sometimes.
My wife uses my penis as her pacifier every single night. She keeps me in her mouth for hours gently suckling on the first 3-5 inches of my penis with her hand on the other 3-5 inches not in her mouth, until she falls asleep; or holding my balls. Once we are both sleep my penis generally stays hard until about 2-3am and then will naturally slip out her mouth and rest somewhere on her face or on my leg. It's such a nice way to go to sleep every night for me and I am glad she gets to satisfy her oral fixation. There is a great hub vid that shows a wife using her husband's penis as her pacifier.