[ Six doesn't need to see the insanity to realize what Sunday likes about his actions. The man goes as far as to point out himself— that he likes his obedience. It's such a strange term to bring up unless that's something Sunday is likely used to, which isn't too farfetched of a thought given how he describes the choice he made under his master's encouragement.

The words leave his mouth before he can even put his mask back on: ]

Does that truly count as your choice if someone influenced you?

[ Sunday gets a glimpse of his expression — a cross between concern and doubt — and then it's gone as soon as Six puts his mask back on. The tension in his shoulders is gone as soon as his face is hidden away again. ]

... A monster shouldn't make themselves so visible. That's all.