LOL at myself!! I actually written a blogpost with incorrect interpretation. So the biggest badasses are characters that have lots of confidence, cool and frequent disregards of authority. I went and wrote about villains instead but no worries I'm writing a new post that fits this category. I will repost that with the proper title instead. There are many characters who fits in this category lately in young adult books. As the urban dictionary most top definition, that person is one ultra-cool motherf*****. So below is my top pick kick ass characters not in any order.
Wolf from Scarlet (The Lunar Chronicles)
A character who is mysterious, strong and fights for a living. This guy never reveals too much and then when he does, well you'll be slightly surprised at his true nature. What he is capable of is what makes him a badass. If I continue more on him I would be spoiling people who will read Scarlet.
Kaz from Six of Crows
A gang leader in the most messed up city. His past which influenced who is he now totally qualifies him as a badass. He has so many tricks up his sleeves that it's hard for people to figure him out. Even with a disability he is able to defend himself which is truly amazing. His mysteriousness totally appeals to me. To know how badass he is, please read Six of Crows which was my favourite book last year.