She would, or at least she should. At the very least as much as he hates himself. Sans really was right in the end, wasn't he? He really did regret it all.

"When I saw what they did to everyone... I... I got really scared."

He sucks in a breath. It causes his chest to sting, but he continues on.

"But then I got really mad. Mad like... I used to get as Flowey. I took one of the human's souls and..."

He rubs at his eyes, his face twisting into helpless anger.

"...I got revenge."