Kenjaku

This would remove him from PE status but its very ambiguous whether its him or not, not entirely possible tho since Rika ate him, maybe its from takaba cursed technique or takaba partner dresses up as kenjaku...

I will wait for anime version to comfirm it because it clears the ambiguity.

Since PEs are mostly exciste to be feared and despiced without having redeeming qualities it's only natural for them having a huge breakdown during their fail. BUT! There's always exceptions - so how about PEs who meet their fail/death with dignity.

My example would be Kenjaku. Despite knowing he is going to die and not see his plan come to fruition, he greets his death with a smile, as he had a lot of fun with a worthy opponent beforehand and his plan will continue even after death. This reaction is even more admirable when you remember that he spent 1000 years (or more) on this plan and that Mahito and Sukuna meet their ends in a much more pitiful manner.

Yuji's dad thought he was sleeping with Kaori. He had no idea that it was Kenjaku. Isn't this objectively a form of rape?

Just an interesting question I wanted to ask y'all, cause some villains are really good at faking politeness.

For me, it's definitely gotta be Kenjaku. I was actually surprised at first when I saw that he was considered faux affably evil instead of genuinely affable on the villains wiki, which goes to show how good he was at pretending to be nice.

If we wanna count NPEs too, then Falcone from the Reevesverse had a pretty convincing impression of a nice guy too.