The Monkey-Cat is a deleted character from the 1986 movie The Fly.
Monkey-Cat was an experimental attempt to test the gene-splicing process for Seth Brundle, now Brundlefly. It was a merger of a Baboon that survived an earlier teleportation and an alley cat. Burndlefly hoped that they would merge at a genetic level. The result was a creature merged back-to-back in excruciating pain. It attacked Brundlefly before he beat it to death with a metal pipe.
It was erased from the final cut after test screenings lost sympathy for the protagonist and some allegedly hurled.