Mac closed her eyes and listened to Jack's playing, soaked in the change of tone and tempo from what he was first playing. She still didn't say a word, there was no need to. Her vulnerabilities and insecurities had been spilled out while she played, and now, much to her surprise, Jack's was starting to spill out too.
After the 'meeting' with Jack's sire and that whole bunch of dysfunctional-ness, Mac knew her master had deep dark secrets tucked securely away inside himself. She normally would have wanted to dig deeper into everything, but after witnessing that interlude and then basically being forced out of the house for periods of time, Mac decided to let sleeping dogs lie. Jack, at least for now, would keep his secrets another day, or week. Or whatever.
Mac was caught of guard when the music stopped; her eyes fluttered open, a bit shocked. The music had been calming. What was that saying? 'Music soothes the savage beast.' Without thought, Mac reached a hand up to catch Jack's wrist, not forcefully or violently, just as a way to make sure he didn't get too far away.