I know what you are thinking, how could a Christian watch a movie called “Kick-Ass”? I can tell you this, it was an interesting adventure for myself. I have always had a strange interaction with film and my faith and this movie was just another “experience” for me in that journey.
On the comic book nerd/action nerd inside of me; I loved this film. Some of the characters did seem a bit “larger” than life (I mean a young girl that trained in violence and weaponry, was a bit far fetched), but that is the nature of comic books. Some of the shots used in this film I found very interesting. Whether it was the motion comic scene (which paid homage to the comic book that it came from) or the night vision raid of the place by Hit Girl, both seemed new to main stream film. 
I felt like the actors did a great job, but I always have some problem with Nicolas Cage as an actor. I have a harder time with some of his roles and in this one; I could not get a real good “feel” for him. His character did not have that much of a back story and I could not find him relatable.
I am happy to see the surge of comic book movies, but I just worry that we are seeing the beginning of the end of it, or perhaps “too much of a good thing.” As more and more comic book movies are being made, I just worry that comic books are going to start changing so that they could be easier to transfer to the big screen.  I do believe that comic books have always had a good pulse on the human struggles of good versus evil; the ideas of justice, vengeance, and identity and other ranges of human emotion. I just worry that as more and more movies are made from comic books, that it might influence the writers of comic books to change their styles so that they are easier to be adapted (but also there is a bit of fanboy in me where I will always see the books as superior to their film and dislike it when people become fans of it, just because they see a movie on it (I’ll stop before I start talking about X Men: Origins).
Now as a Christian, I had an inner battle. I wanted to enjoy the experience as a short glimpse into human emotion (the battle between good and evil, the weak standing up against the strong, the fight against injustice). But at times, I was shocked by the use of coarse language and extreme violence.  Of course, I knew this going in and the issue wasn’t that I was shocked because of what I was seeing, but rather, I was shocked because of how it didn’t affect me. Have I come to a place in my own faith where seeing extreme violence or hearing coarse language doesn’t affect me? Even if it is on the screen and I do not practice these things myself, am I supporting some kind of evil system that will keep on making things more coarse and more violent to get that same “shock effect”? I went to see the movie with a group of Christian guys and the discussion after the movie wasn’t about being offended, it was about how  “awesome” some of the stunts or action sequences were. In fact, one of them was more offended by the pseudo-sex scene rather than people being graphically murdered.  These questions are difficult for me, as I watch society push and push the envelope further and as a Christian, I feel like I am part of this world…but yet at the same time, I feel like it is “ok” (or even “awesome”) because I am not actually doing the things depicted. 
But upon further contemplation I began to think about the Biblical stories, where perhaps there isn’t as much coarse language (well not the way that contemporary coarse language sounds), but there is violence. We as Christians are told to internalize these stories as they reveal to us the deeper truth of understanding God and perhaps my own view on violence in the media is affected by that.  Well, it is more to think about.
All in all, I would say for the secular comicbook nerdness of the movie, you could go see it, but you should be forewarned for the violence and language. But at the same time, there is a story of justice and standing up for the weak, that I do believe that society needs to hear. But as a Christian? I would say, enjoy dialoguing with the movie and seeing what offends you and why?