"None." She could say that much confidently enough. "I used to be able to make it go back inside, or calm down, but not any more. I could barely do it at all when it attacked Flauros a few months ago..." Yako flinched.
It probably wasn't a good idea to tell your boss that you literally got into a fight with a co-worker, even if you weren't in control of yourself at the time.
"That was the first time I had seen the...the Blood. I don't...I heal fast enough that I never had the chance, before then." He should already know that much about her, at least.