NPC is a meme. Your link to urbandictionary is particularly interesting if you look at the contributors history...
NPC left is a term specifically to fuzz anti-progressive animus through 'memeing' language. This type of coded language is a common tactic of white supremacists [0-4]. You may have done it intentionally or not, but it is what it is [0,1,3]. If this is unintentional, you should be aware that that language is created specifically to play with this irony and ambiguity and draw people in while taking a stance that enables everyone involved to claim [4].
[0] https://www.lawfareblog.com/how-white-supremacists-use-soft-...
[1] https://www.npr.org/2021/04/26/990274685/how-extremists-weap...
[2] https://www.latimes.com/nation/la-na-pol-alt-right-terminolo...
[3] https://mashable.com/2017/05/05/alt-right-memes-france-world...