My fiancee accidentally sent my adult niece (early 20s) a picture of me. My niece has no filter, and I felt that, while painful, the best thing to do was say something to my brother and sister-in-law before my niece said something without the full context. I could 100% see my SIL looking at her phone and my niece's answer being it is uncle Indym.
My brother was not mad, and my sister-in-law acted briefly miffed about it. My niece promised to delete it, but I think my SIL saw it. I'm not shy, but it felt a little awkward the next time we were together.
To answer the OPs question, I'd have to put my niece pretty high on the list of who I didn't want to see, and it is no fantasy of mine for her to see me.