What was the Keymaster's deal? *SPOILERS*

[Taijitu Taikyokuzu]

So after Edna finds that pastor guy, she goes out and finds that the Keymaster has murdered him, afterwards the Keymaster seems pissed at Edna for letting him out. Why did he kill the guy in the first place? I know he was insane, but don't insane people usually have some kind of logic to what they do? He doesn't seem like he just snapped and killed the guy, if he had, he probably would've tried to kill Edna too. Is there some kind of psychological condition that actually makes people behave this way?

[Michaelus]

He's justifying himself and thinks it's Edna's fault, not his. He seems to be aware of his condition, but can't help the urge. After urge is temporarily satiated he feels guilty and projects it on someone else.

edit: it felt kind of forced into the game anyway

[Taijitu Taikyokuzu]

Do crazy people ever do that in real life?

[Michaelus]

Why not? After all it's normal for majority of people (projection and satiating urges). Only difference is they don't have mental blocks to murder others. Not that such blocks are hard to remove e.g. soldiers.

[TenOfPrime]

While the rare exception it can indeed occur, perhaps he just gets random urges to kill every now and then or he has a mental disorder that makes him prone to psychotic rages and the guy in the church just set him off by saying hi. Insane people normally do have a logic behind them but if that logic is sound is a different issue, I think it is telling that out of everyone in the place he was the only one other than Edna who was kept in a locked cell. I knew from the start that he was trouble but you have no option but to free him.

[Doggy Davis]

He hates rock and roll music, which the pastor has a lot of.

[Taijitu Taikyokuzu]

Holy crap, that actually makes a lot of sense.