Im gunna use some language in this comment, so if you're easily offended skip it! NSFW
I'm a big fan of TWD, both TV shows and the comic books, and I gotta say that while at times, especially in the books, I wished and hoped for Negans demise, I do love him.
Of course in the books they can do a lot more with all the characters, especially in regard to use of language- it's a fucking fuck fest of colourful language, which in itself can be amusing, and somehow endearing to my childish mind. So while on the TV Neagan says things like "Pee pee pants city", in the books (he does say that) but he can use lines like "Mother fucking dick suck cunt fucking fuck fuckity fuck fucker fucking fuck fuckers!" (and that is a direct quote from the comic books)
So I think for me the endearing aspects of this particular character are his funny and creative ways to use swear words as nouns, pronouns, verbs, adverbs and adjectives all in one sentence.
I just wanna say, always feel free to use any kind of langauge you want.
I even wrote a short comedy once about the word "Fuck" :)
https://steemit.com/life/@the-alien/political-correctness-from-a-strictly-extraterrestrial-point-of-view