A flesh addict within the context of sex and sexual encounter can be described as a sex addict.

In a more literally sense Tank Dempsy used it around the end of the ww2 to describe what appeared to be hords of Nazi Zombies that where attacking him and his friends.
DIE YOU UNDEAD FLESH ADDICT!!!!

COME GEY SOME FLESH ADDICTS!!!
by iron13 June 15, 2011
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