As she posits that he might be crazy, Strange shakes his head. "I know what madness feels like. When I saw that image in the mirror, I was perfectly sane."

Which opens up a few more questions about his past. Still, he's hoping that Billie's complete disinterest in talking about things includes a disinterest in talking about him. The fact that her scale was black is unexpected: this is the first time he's heard of the scales being other colors. Strange can't help but look interested for a moment before he continues talking.

"The scale was white. But considering that a few months back I received a message from Logistykon, the white dragon, I expected that." All of this was connected in some way, Strange just had to figure out to what extent.