I’ll tell you a medieval secret — I know a lot of them — the reason that medieval builders, artists and poets were so superstitious about the number seven is that it was so difficult for them to deal with it. Try doing long division (iron division, we called it then) with seven in Roman numerals. So very unpleasant, we only did it during Lent. Try dividing things with seven on a pocket calculator. Even when expressed in the ho-hum, prosaic Arabic numerals, the beauty of the repeating decimals will give you the mystical willies, tell you what.
It’s an odd number, seven is.
If you draw a heptagon (or better, fold one) and connect every second corner, you’ll get a lovely heptagram. If you connect every third corner, you get a different, but no less lovely heptagram.
If you fold the first heptagram and than fold the other heptagram inside it, well, you’ll get this model. Spooky, hunh?
Almost certainly a variation of an existing fold.