A person who is just too great and perfect for words that you have to make up a word because nothing else fits their perfection.

Tip: If you ever meet a "Nennin" you have literally been blessed by god, him/ her self.
Person 1: " I feel like Nennin"
Person 2: "That's impossible, no one can be as perfect as Nennin. Stop joking around, it's not funny."
Person 1: "Yeah, your right."