Claude being a murdering bastard already doesn't really surprise me, although it's a bit of an asspull.
This manga is very heavy on the "Repentance/Redemption/Forgiveness" trope, irritatingly so sometimes.
And Claude needs to be portrayed in such a way that he can be killed off in a way that doesn't break that trope. He must be Irredeemable.
Last chapter we saw the other members being killed by him after they got their little Repentance/Redemption Moment ( and death sentence by Plot Device..) by Claude in a rage.
But killing in a rage is, while definitely Frowned Upon, at least understandable. It's one of the very few excuses one can have for killing someone that can possibly reduce sentences.. Because Redemption is ( at least theoretically..) still possible.
It still gives a Lawyer something to work with. Devil's Advocate, and all that. Dirty Job, but...
Anything Claude has shown up until now can still be explained by overblown Ego and misplaced entitlement leading to his attitude and explosions.
But cold-blooded murder? Simply because someone has a conscience and tries to get in your way?
That's true psychopath territory. There's no saving
those.
Which may have ( at least I hope so ) one very big advantage: Very little chance of a Sob Story background flashback for Claude explaining why-he-became-who-he-was.
Looks like we'll be saved that exercise in story stretching and tedium...
The way it was delivered, though.... Euuurrghhh!