It features JADE embodying American musician Diana Ross during the disco era in the 1970s, with references made to the 1976 film Carrie.

They drew musical comparisons to American acts including Chic, Nile Rodgers, Mariah Carey and to English singer Raye concluding that it had influences of 1970's funk, and 1980's post-disco.

[15] Writing for Clash, Shahzaib Hussain wrote "'Fantasy' is an irresistible assemblage of post-gay disco liberation, processed by ASMR purrs and ecstatic vocal ululations, all melting into a euphoric club-ready mix that speaks to the judgement free zone JADE is rendering".

[17] On 25 October, Thirlwall performed "Fantasy" and a cover of "Backbone" by Chase & Status and Stormzy on BBC Radio 1's Live Lounge.

[18] On 31 December, Thirlwall performed "Fantasy" and a medley cover of "Hot Stuff" by Donna Summer and "Knock on Wood" by Eddie Floyd on Jools' Annual Hootenanny.