Am I doing this wrong? Feeling stuck with ComfyUI and realistic AI content for my app

I’ve been trying to create realistic AI images in ComfyUI for content that I want to use to promote my app on TikTok and Reels. The goal is not just to make something flashy, but something that feels believable and high quality enough to actually work as advertising. For example, I’m trying to make a scene of a girl taking a mirror selfie in a bikini, and then turn it into a two-image setup: one version where she’s unbranded/un-tanned, and another where she looks tanned, so the contrast in skin tone is clearly visible.