Jack Gleeson is known to the world as the little blonde brat on "Game of Thrones," Joffrey Baratheon, aka King of the Iron Throne, aka Lord of the Seven Kingdoms, aka any other moniker this child doesn't deserve.
In the upcoming Season 4, Joffrey is about to get married and thus makes everything about himself, as usual. While Gleeson is definitely not anything like Joffrey in real life -- he's studying philosophy at Dublin's Trinity College; he has a lot of smart stuff to say about pop culture; just look how innocent he was in "Batman Begins" -- he did have a bit of a mean streak once.
In an interview with Entertainment Weekly, Gleeson shared the meanest things he's ever done in real life, and while no comparison to Joffrey's tyrannical brattiness, they're kind of messed up. "I read my sister’s diary when I was 7. She was, I think, 13. It was awful to read it," he told EW. Yeah, Gleeson, that's totally not cool.
But Gleeson did something even worse, even more scarring, and almost entirely unforgivable. He ruined the ending of a "Harry Potter" book for the same sister by telling her Sirius Black dies when she was only halfway through reading. We fully support said sister if she still hasn't pardoned Gleeson for his crimes.
At least he didn't spoil Dumbledore's death though; if so we hope his sister would've gone full Tyrion on him.
Season 4 of "Game of Thrones" premieres April 6 at 9 p.m. EDT on HBO.