It can have many different meanings.
Usually replaces the word "fuck" in a language called flernglish, so that you can freely "curse" without actually "cursing", because nobody knows wtf you are saying.
If said in the sense of something being "flarky" then it means cool or awesome.
Person A: Dude, I totally flarked that girl in the ars!
Person B: Dude, Thats the same girl that I flarked in the ars! That is so flarky!
Staying up all night doing meaningless tasks that you would'nt normally do during the day.
Or if said in a sense of "kyling", then you probably missed the show Kyle XY, and are forced to stay up late to watch the repeat, in which then you would stay up after it is already over, and still do meaningless tasks anyways, regardless if it is a school night or not.
Also See: kyling
Person A: Dude, I pulled an allnighter last night, cuz I missed Kyle XY, and I saw it at midnight, so I could'nt sleep after that.
Person B: Me too, we were actually on the phone last night, talking about Jlirmmy...
Verb. To kyle.
The act of staying up really late at night doing meaningless tasks that you would'nt normally do during the day.
Or if said in a sense of "pulling a kyle", then it means the same thing as pulling an allnighter.
Person A: Wow, I pulled a huge kyle last night.
Person B: Dude, you gotta stop kyling, its killing you!