look up any word, like cunt:
 
1.
twins having sex.. its so wrong, yet it feels so right
me and my twin have twincest. i fuck my twin, and enjoy it.
by nadia_aidian February 28, 2004
 
2.
When twins are in lust/love with eachother.
by Anonymous September 14, 2003
 
3.
When Twins are in love with one another and/ or like to perform sexuall activities together.
Benji and Joel are in alot of Twincest fics.
by Rhiannon December 08, 2003
 
4.
the hottest damn thing ever!
In The anime/manga series Ouran High School Host Club the Hitachiin twins(Kaoru and Hikaru) were called out on there twincest by Kirimi Nekozawa.
by sourxneonxgummixworms June 14, 2009
 
5.
incest between twins.
twins who have a sexual relationship
Benji madden + joel madden = yummy twincest
by squee February 19, 2005
 
6.
Incest between twins. In the world of fanfiction, this is both a frequent and yummy occurance that we, as human beings, should be eternally grateful for. <3
Hizashi/Hiashi is mad twincest. <3
by Louey March 23, 2007
 
7.
Twincest
Gives new meaning to fo fuck yourself.
TWINCEST example: Hikaru Hitachiin and Kaoru Hitachiin
(if you dont know who they are, LOOK THEM UP)
by ASIAN >.< Wu-Dawgg May 07, 2010