I would ask your vet . Having him neutered should not make him bite.
I got my kitten as a rescue at 2 weeks old. She is now just a tad over a year. Her biting is also constant...like she is teething. She never really tries to hurt but there are times she gets rough. I found that restraining the cat with your hand on your lap and scratching or stroking helps calm my cat and she settles. Hope it helps.
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