recently i saw someone called tsukishiro_saika on twitter that have similar style with the old artist called s-syogo.
on this tweet, they mentioned about 2 years ago illustration that makes me wonder about syogo's final clue on their final art before the deletion (post #1901736).
i feel that kind of background looks familiar like what s-syogo always uses on some of his art like post #1765794 this one.
knowing both of them sometimes draw bondage or torn_clothes let my speculation that syogo comes back to the pixiv and twitter with another name (not bottomash one) that focuses on vocaloid (also dragon project that they keep mentioning about) instead of touhou. (i'm not sure if this fits as alias request)