yes, he WILL breed before she is BIG ENOUGH (not old enough) to be breed.
Plus if you keep 2 snakes in the same cage (unless breeding) then you can't tell who has poo'ed and who hasn't or who pee'd.
If one is sick and has runny stool you don't know which it is, so you have to take BOTH to the vet (doube the vet bill).
SNAKES ARE SOLITARY ANIMALS. THEY DO NOT NEED THE COMPANY OF ANOTHER SNAKE.
The reason you see them "sleeping together" is because that is the best hot spot/cool spot in the cage.
It is WAY to easy and WAY TO CHEAP to be able to go get a rubbermaid and drill some holes in it.
If you can't afford 2 cages, you can't afford 2 snakes.
There are to many risks for the snakes to house them together.
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1.1 Ball Python, 0.1 motley amel corn, 1.0 western hognose, 1.0 red blood