Aaron is talking to Damon in this scene from The Vampire Diaries. It's from the episode "The Cell."
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Aaron will continue to play a key role on The Vampire Diaries. He's played by Shaun Sipos.
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Stefan is front and center in this Vampire Diaries scene. He is next to Aaron and Damon.
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The Vampire Diaries Season 5 Episode 10 Quotes

Damon: I'm gonna barf.
Katherine: Great. Then my work here is done.

That's my brother Stefan. But I'd watch your tone with him because he's kind in the middle of a psychotic break.

Damon