Double 0ne

On January 17, 2025, PocketDol Studio revealed that BAE173 will be collaborating with FANTASY BOYS for a release sometime in March or April. BAE173 member J-Min would not be participating in this project as he will focus on promoting with CLOSE YOUR EYES, and BAE173 member Hangyul would not be participating either in preparation for POLARIX's debut. On March 1, 2025, PocketDol Studio unveiled teaser clips for the collaboration group named Double 0ne, and their upcoming release "On the Rocks with Kiss", scheduled for May.

On May 2, an article from Starnews Korea mentioned that Double 0ne would make its debut in the second half of the year. On May 13, an article from Ilgan Sports reported that Double 0ne would make its debut on June 12, 2025. On May 9, PocketDol Studio announced that teasers for the songs "Reserved", sung by BAE173, and "Toxic Lips", sung by FANTASY BOYS, would be released the next day as part of the project collaboration.