Muffing is an erotic and unusual form of penetration. Involving insertion of a finger into one or both of the inguinal canals. It is a sexual technique popularized by trans women, and is unique in that it is completely dry. No bodily fluids are involved. It requires the inverting of scrotal tissue and pushing it up into the cavity (or cavities) through which the testes descended before birth or in early childhood. In some ways, muffing has more in common with CBT (Cock