As Charmander took the liberty of rolling over for belly rubs and the girl decided to take a seat beside him, Cash couldn't help but smile to himself at the similarities. It seemed like both owner and dog were comfortable with others and had no problem being openly friendly. A fact he really like considering that's how he was.
His hands moved obligingly over the dog's belly, laughing lightly every so often at a noise from Charmander or a gesture to 'not stop'. Turning to the girl when she spoke, he smiled reassuringly. "It could definitely be bad. Some people are just cruel when it comes to animals," he remarked, expression sobering a little for a moment before he realized how he sounded. "Not that I'm trying to scold you! That sounded bad," he corrected, looking instantly apologetic and sheepish.
He was distracted from his mortification by her questions, though still hoped she didn't think he was some weird tight ass or something. "It's part of my abilities," he explained. "I can transform sound, or sound waves more specifically, into light." He smiled, letting her know he wasn't bothered by the questions either.
"No no! It's not rude. Curiosity is the spice of life," he assured her with a grin. "I'm Cash." Taking her hand, he shook it with a smile that never quite left his face in place.