Klaus found himself wondering what that would be like, admittedly he didn't know anything about magic, not real magic - people thought what he and his siblings could do was something like magic, but he knew the difference. But to be from a place so different from the one he'd grown up in. He didn't know how he'd have turned out.
While Regulus listened Klaus leaned in close enough to be able to hear just enough so that when he hummed along to the familiar tune he wasn't too far off as he did. His head tipped back and eyes closed as he enjoyed it. This place was too quiet for Klaus so a little music was just what the doctor ordered.
And when he felt Regulus reach out, Klaus let their fingers tangle together and gave him a reassuring squeeze. He didn't know for sure what Regulus was feeling but it was pretty obvious that he was feeling something as he listened. And that was the point wasn't it? You dulled everything you felt with drugs then listened to music to feel something again, at least that was how it worked for Klaus, of course these days he was skipping the first step. At least for the moment. He still wasn't sure how long that would last, but with his spoils maybe he could draw it out a little longer.