it is a mystery and as such
DeTeCtTiVe pythons is on the case
this thread is speculative so no flaming plesa

hypotheses:
a) failfailfailfailfailfailfailfailfailfailfailfailFa
AA) kain is going through puberty; scared to talk to girls :^(
AB) jess' vagina is floppier than his
AC) small droopy dick
D) his tits aren't as big as hers
E) his mother never hugged him enough as a child, and he is projecting it onto jess, Freudian style
G) ??? (as of yet undiscovered theory, possibly the next element on the periodic table?)
F) there is no F because F stands for fail and ptyhons doesnt fail
PS
as of august 08 2009 " i have my reasons" is no longer valid please renew your excuse within the time allotted