What is Selfcest?
1.
Slashfic where a character is paired romantically or sexually with himself.
The most ridiculous, least socially accepted, and therefore the
hottest kind of pairing (im)possible.
"Do you ship Sam/Dean from Supernatural?"
"Nah, Wincest just isn't wrong enough. I ship Sylar/Gabriel Grey."
"Oh, selfcest, huh? Hot!"
See
2.
The sexual attraction to ones self
She was caught engaging in selfcest activities
See