Comedy Central's roasts can be pretty brutal. So who better to ask for advice on jokes that'll really hit someone at their core than that person's ex? That's exactly the thought process comedian Jeff Ross had when he asked Selena Gomez for her advice on how best to roast Justin Bieber.

Ross spoke wit the Huffington Post about the upcoming Bieber roast earlier this week (March 24), as well as roasts in general. It's an interesting look into the work that goes into berating a celebrity on national television. For example, when asked how soon he starts writing jokes Ross said, "Well, the way my brain works, it starts immediately when I hear the name. I can't help it. I don't have a filter to keep me from thinking of how to take that person on. So, I start as soon as I hear the announcement or even when they're just thinking about that person, I start coming up with jokes in my head."

The juiciest information Ross gave the Huffington Post has to do with running into Bieber's ex-gilrfriend, Selena, and asking for her advice. What did she suggest? Ross says, "...she said, 'Tell the truth. That's always worked for me.'"

Ross went on to say that doing the roast with Justin endeared him to the singer. Justin even had some good rebuttals of his own. He said, "He had some killer roast jokes back at everyone and then he crushed everybody with his sincerity. I thought it was a winning effort for him. I think people are going to dig the way he handled it. I mean, what were you doing when you were 21? Figuring out how to atone for your sins? At the end of the day he's just a young man with a big heart and a lot of fans. I just kind of saw him as a normal guy."

You can check out the full interview over at the Huffington Post. And be sure to check out Justin's roast when it airs on Monday (March 30)!

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