A round flash head produces a light patter like this: ( )
A rectangular flash head produces a flash pattern like this: [ ]
Both are fine and are only noticeable is your subject is very close to a background and even then not much.
Personally I prefer round in studio and standard for editorial stuff because the flash can “zoom” or create a narrower beam of light.
Edit them out of the picture, leaving only a silhouette, and post it with the caption “ghosted” haha then include a little story about the place, why you liked the photo or location, what it feels like to be ghosted. Have fun with it.
No permission is violated but it makes a good photo/story.