He was soft spoken and mild mannered by nature, because his father was the complete opposite. Usually in those situations, the children grow up to be just like their parents, but in Bruce's case he vowed never to be that angry, so he stored all of his anger and hatred deep down within himself, which spawned the green rage beast that they were talking about today due to that freak accident and of course a problem with his genes that actually kept the radiation from killing him.
"Only when I'm upset or angry." He explained, before shaking his head at her, "no, right now I have no control over it, but I try." He told her, and that was true, he tried but the rage was too overpowering for him to fight or control it.
It was definitely a he, and he considered it both a part of himself as well as a separate being, considering all they shared was a body. The Hulk possessed no genius level thinking ability, like he did, nor did it seem to have any other emotional range other than just rage and anger.