"I can see it in your heart; you're a good person and are young." He said, "I'd be a horrible human being if I were to destroy someone with as kind and young a soul as your's just because of what you are."
"I am not going to try and deliver such cruel actions towards others unless they forced me to do so." BlackBelt told him, "You are like a child and that means you have so much potential for good and it'd be wrong to not allow such a life to be cut short because of fear of something that may never happen."
Brock could probably feel BlackBelt was trying to comfort him and be a friend rather than to act as judge, hurry and executioner to a child because of their 'species/race'.