You know, Alice should have realized that no matter what answer he gave, there was no plausible explanation for getting 'back on track' that was a nice, happy one. Still, she was shocked by the idea of Boo fighting people, for a living and otherwise. Sure, he was, you know, insanely well built for it, and that much made complete sense, but he just seemed... nice. Nice with an edge, maybe, but nice.
"Wow," she finally answered, taking a sip of her coffee to give her a moment to gather her thoughts and come up with something with more than one syllable. "I'm sorry, I'm just really surprised by that. But... I'm glad you decided to give yoga a shot." She managed to keep to herself the super cheesy afterthought of 'and glad I showed up to your class', but it still made her smile.