So he only has two hens he can breed at the moment. That's not nearly enough. The pullets are far too young for him. Somehow he's intimidating or terrorizing this one hen. That's why @nuthatched gave you the solution to the problem in post #5. Separate the rooster until the younger pullets begin to lay eggs so he can spread his affections among more females. They are at least five months away from being breedable. Or find him another home with a bigger flock, and give your girls some peace and safety.