No, I don't think he's human or at least not entirely human. Part of my issue with Kajia, MC's parents, and the Templars is that I still don't think they're being completely honest with him. I even think it's possible that Kajia was monitoring him but not guarding him and the reason she panicked the night he was ambushed wasn't because he was actually in much danger but because she wanted to prevent him from shedding blood. She got very upset when MC shot the mercenary - and it was shortly after that MC started displaying magical powers.