Ariana Grande As Alexa Armstrong On 'Ew!' With Jimmy Fallon

Singer Ariana Grande (C) performs during the 2014 Victoria's Secret Fashion Show in London — Singer Ariana Grande (R) performs as model Candice Swanepoel presents a creation during the 2014 Victoria's Secret Fashion Show in London December 2, 2014. REUTERS/Suzanne Plunkett

Ariana Grande unleashed the Nickelodeon inside her as she dropped by "The Tonight Show Starring Jimmy Fallon" Saturday night as the latest BFF of Fallon’s character Sara on the recurring tween talk show “Ew!” The pop singer played Alexa Armstrong, barely making it through the skit as she lost herself in some ridiculous moments.

During the skit, Sara, a teen girl with an obsession for selfies and the social media, introduced her new BFF Alexa Armstrong as they performed their secret handshake, Us Magazine reported. Fallon and Grande shared a number of toppling-over-a-chair-laughing moments, including one where his character Sara challenged Grande’s character Alexa to the new segment “The Ew! Sing-off!" Alexa showed off her angelic vocals, totally topping Sara’s swan song, even if she didn’t think she could. They also broke character as they played a game of “Ew Speed Round,” where Sara proceeded to show Alexa a picture of a neck pillow, to which Alexa responded with "ew!," and a venti latte, which she responded saying she preferred grande, Entertainment Weekly stated. Alexa also took to Richard Dreyfuss' defense to say he was cute and a “really talented actor” when she was showed a photo of him.

Grande obviously couldn’t contain herself anymore as she doubled in laughter, hardly managing to keep up with the sketch. The “gals” then snapped a "best friends forever selfie,” or a "bffelfie" for short, which they posted on Instagram. They also got freaked out when they saw that one of Alexa’s photos only had three likes.

Earlier in the show, the “Problem” singer did a Celine Dion impression, and received good feedback from the audience. Grande is the latest BFF guest on the “Ew!” couch, which previously seated Taylor Swft, Zac Efron, Emma Stone and First Lady Michelle Obama, among others. "The Tonight Show Starring Jimmy Fallon" airs weeknights at 11:35 p.m. on NBC.

Watch Ariana Grande as Alexa Armstrong in "Ew!"