The female in the pic is either already gravid by him and shes just refusing his advances, or shes just gotten her blush color and is ovulating and he is wanting her badly, LOL
As far as male aggresion if he continues this and you see her neck bleeding or he draws blood or wounds her anywhere seperate them.
I have a male that sometimes mauls the female and has left them badly hurt bleeding and ripped up at times.
I do not think it is worth it, and just keep him with another male buddy now , no females in his life anymore.
Let us know how it goes, they are quite pretty both of them 
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PHEve / Eve
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