Seeing how Christopher's face lit up when he laughed made Sebastian wish he could make him laugh often. It was a beautiful thing to see. He told himself to snap out of it, knowing what a fool he could be for a pretty face.
"Forewarned is forearmed," he said, still on the joke. But then he offered the true answer anyway. "Actually, I always excelled at the physical stuff, and everything to do with hand-eye coordination. Tactical was a breeze. Other things I had to work at more. So one of my teachers at the Academy took me aside one day and suggested I explore that area more, said I had a real aptitude for it. The rest is history."
Sebastian was very much an alpha male, and as such, it gave him great pleasure feeling like he was keeping his clan safe. It was a very ancient, instinctual need in him, to be a protector. But he didn't need to spell any of this out to anyone, nor was he completely conscious of all of it either.