Stein nodded thoughtfully. "How come you never infected yourself with it?" he asked with curiosity. Perhaps it was just very dangerous, but certainly regenerative abilities and super-strength was worth a bit of risk.

He blinked. Why was Birkin getting so upset? Stein obviously didn't think being a sociopath was such a bad thing, so he couldn't think he was being deliberately insulted.

"Why does it bother you so much if you are?" he asked.