The same year, she co-performed with American EDM duo LMFAO on their hit single "Champagne Showers", which became her most successful recording to date.

[6] She adopted the first name Teddy in 2015 and formed her own band Cruel Youth the following year, with whom she's released the extended play (EP), +30mg (2016).

In March 2015, Sinclair and her husband Willy Moon were fired as co-judges from New Zealand X Factor for their harsh comments towards a contestant.

[16] She began pursuing a music career and had a significant breakthrough as "Candy Rapper" in 2003, when she won a BBC Radio 1 MC Battle in Leeds.

[17] She signed to the UK record company Adventures in Music and released her first single "Don't Play Nice" under the name Verbalicious in February 2005.

[18] During this time, using the name Verse, she also co-wrote and appeared on "They Talk Shit About Me" by French recording artist M. Pokora and met Guillaume Doubet, who would go on to direct many of her videos, in Paris.

[28] Sinclair attended an after-party for the 2013 MTV Video Music Awards, held on 25 August 2013 in Brooklyn, New York City, where she performed various songs from Trouble.

[7] Sinclair described Irvine as a doppelganger over his alleged copying of Moon's hairstyle and dress sense, deeming him "cheesy" and "disgusting".

[34] The comments led to widespread condemnation on social media, including a petition to have Sinclair and Moon fired from the show, which reportedly received over 70,000 signatures within 24 hours.

[44] In 2022, Sinclair and Moon received songwriting credits for "The Happiest Girl" on Blackpink's Born Pink[45] album and released the single "Mr. Badman" in 2022 as part of the soundtrack for The Invitation.

[46][better source needed] In 2023, Cruel Youth released the single "Sunny", a cover of the same-titled song by Bobby Hebb.

Sinclair has mentioned Kate Bush and Alanis Morissette as her most important musical influences, describing them as emotional artists "who write honestly about their opinions and experiences.

[49] According to Jon O'Brien of AllMusic, Sinclair gradually composed a musical tone incorporating "the theatrical dance-pop of Lady Gaga, 1940s film noir, and the electro-gloom of Depeche Mode.