Tease the new villian 2

To see what happened to Chrysalis "[link]"

Even though I was kinda busy, I still felt an urge to do this comic. XD

Well, I was worried that the words in third panel are too vulgar since its reference is from a movie whose movie rating is R. But then again, I want to stick to its reference([link]) or it might not be funny. Plus , flank simply means a horse's side, not its hips. So I guess it is Okay.

Now I mention it. I am always wondering why people use flank to substitute for hip. According to dictionaries, flank means the side of something. I looked up several dictionaries and very little of their explanation evolved anything pertaining to buttocks. At most, They only speak of flank is an animal's or person's body, between the ribs and the hip specifically. Even though the location of cutie mark is a bit closer to hip, they are still located on the sides which are the flank's real meaning. Is it because people using it to avoid vulgarity, like heck instead of hell and frigrin instead of f***, I wonder?

Also, since I am not a native English speaker. I was in trouble understanding how serious the language might be. I looked up Wiki's page for Profanity. It says "Kiss my A**" are usually considered mild. However, as I searched more on the Internet, I found that people would still censor it. This make me confuse. Exactly how serious is the word "a**" ?

I know sometimes language could be some wonderful materials for comedy, but I am worry if I don't manage it well, it could only make people uncomfortable. So I just want to ask if anyone could explain a little about the level of profanity? Thanks.

Update in 2012.11.27
Thanks everyone for answering my question. I was only hope that my works would not offend people, but now I can see that everyone is OK with this. I just need to be careful if my work were meant for younger audiences.(Guess that's why everyone all says that Internet is not safe for children)