it sounds like they're both to small to be mating, maybe the male is just really hungry, or unusually aggresive. Either way, I'd make sure that they are always separated and in different cages.
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My menagerie
1.1 Ball Pythons
1.0 Amazon Tree Boa
1.0 Corn Snake
1.0 Dumeril's Boa
1.2 Bearded Dragons
2.1 Crested Geckos
2.1 Sudan Plated Lizards
0.0.5 Eastern Painted Turtles
1.2.5 Eastern Box Turtles
1.1 Eastern Red-spotted Newts
1.0 Northern Mockingbird
0.3 Chickens
2.0 Cats
1.1 Ferrets
0.1.4 Wild mice
0.0.35 some kind of goldfish