My Dress-Up Darling XOXO! gathers comedic side stories featuring Marin Kitagawa, Wakana Gojo, the Inui sisters, Amane Himeno, and other familiar faces from the cosplay community around them. The anthology-like spin-off turns friendships, hobbies, school life, conventions, and costume-making into short exaggerated misadventures, offering a playful alternate look at the cast rather than extending one continuous main-story arc.