The kinky act of when a man inserts his penis in his own ass.
The penis is
typically flaccid as that is when it is at its most
flexible, and is bent inwards or downwards to meet the asshole.
Autopenetration is synonymous with the action to self-fuck. Although getting
the penis inside the asshole is not that hard at all if the penis is at a decent size and proper lube is used, it is
difficult and uncommon to be able to do this to orgasm, as the penis
generally stiffens while getting erect and loses the ability to bend down and inwards.