"When I'm done with this, it'll make the worst player sound good." Her hinted challenge was something that he could've easily taken offensively. Just because he was poorer didn't mean he wasn't talented. Michel would've pulled out the cheaper, but still sturdy, violin he owned to show that he was capable, but she noticed something that he hadn't thought about it until she brought it up. He did have her painting sitting right there. If he had known she was coming or thought about it afterwards he would've hidden it somewhere. Though there was no reason to feel any shame in having it. He just didn't want to send any mixed signals.
Finally setting everything down and turning to look at her again. "Last time I checked it's not yours," he replied, making it clear that she lacked ownership even if she painted it. "It's Paris's painting. And you have nothing to do with it being here." For the most part, the majority of her paintings were ashes unless there was something somebody wanted to keep. He may have been behind organizing the destruction of them, but even he couldn't watch that particular painting burn. There were plenty of paintings of Paris around the city and certainly most anyone who was skilled enough with a paint brush could obtain one. But it wouldn't be like that. And not at night. He could appreciate it for what it was, even if she had been its artist.