The shape of Latin S arises from Greek Σ by dropping just one out of your 4 strokes of that letter. The (angular) S-condition made up of 3 strokes existed for a variant of your 4-stroke letter Σ now in the epigraphy of Western Greek alphabets, as well as the https://milowmcsg.uzblog.net/everything-about-bud-naked-exotic-45358669