The shape of Latin S arises from Greek Σ by dropping a single out on the four strokes of that letter. The (angular) S-shape made up of a few strokes existed to be a variant of the 4-stroke letter Σ already within the epigraphy of Western Greek alphabets, along with https://stephenukzqe.blogolize.com/rumored-buzz-on-bud-naked-70576817