J.K. Lolling 

A play on the English writer J.K. Rowling's (writer of the Harry Potter Series) name. It usually means "Just kidding, and I am laughing aloud at the same time" or just "I am currently laughing aloud".

Frank: Dude you're such an asshole sometimes, you know Sarah and I broke up last week.

Joe: I was J.K. Lolling (insert emphasis here).

J.K. Lolling by Baeowulf February 23, 2008

J.K. Loling 

Openly making jokes about Harry Potter related books/movies in front of fans and responding with "J.K. Loling" in order to prevent that said fan from hating you.

In short: "I'm just kidding. Your reaction was funny, though."

guy: dude the harry potter movies suck, i could play the characters so much better even without a script, they are all stupid they suck so much

fan: WTF MAN IMMA KILL U

guy: J.K. Loling

J.K. Loling by ssplice November 4, 2010

J.K. Lowling 

J.K. Rowling, Author of the popular Harry Potter books, when she's fucking with the minds of her fans regarding new releases, e.g. teasing about new possible books, Pottermore information, etc.

Samantha, Rabid Fangirl: GODDAMNIT I GOT AN EMAIL FROM POTTERMORE AND I THOUGHT I WAS IN THE BETA BUT IT WAS JUST TELLING ME THAT I WILL BE GETTING ANOTHER EMAIL THAT WILL BE THE ACTUAL EMAIL. THEN I GOT ANOTHER EMAIL AND IT WAS TELLING ME THAT THEY WERE PREPARING TO SEND THE EMAIL. FUCK.

Ryan: Yup, that author is just bein' J.K. Lowling like crazy.

J.K. Lowling by Apokamptos August 29, 2011