Looking for a manga with chaotic evil mc.
By "chaotic evil" I mean someone doing things for fun or for selfish goal/his or her own interest, with no real justification or noble goal. Best examples I can think of are Shamo and Murcielago, although in last one .

It can be a slow corruption path too, but without a 180 degree turn around.

Already know about this one and one about demon lord manga with absurdly long name too.

Have you tried checking tags like "Cruel male lead" or "evil protagonist"?

It's a webtoon and a comedy one, but if you don't mind:

The Devil King is bored

oh, yeah and the guy from my avatar is from a comic called
"Looking for group"
and he's an evil asshole. Pretty funny though.

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