Yumeko Kuketshiki

Origin
Kuketshiki Yumeko, is the corrupted or creepy version of the original yumeko jabami in the anime named kakegurui, she is a fictional character involve in a game with an unknown name and mysterious theme including other fictional character like Hinata Kuketshiki EXE, Mary Kuketshiki EXE and etc.

It is said that this corrupted version of yumeko is posting cringe stuff in it's facebook page named 666.Yumeko. EXE.

As what we know "666" is  devil number and "EXE" is what we know as Virus/computer file or a cursed

Back Story
So in the story it said that yumeko agreed or have a deal that she will be very skillfull in gambling or what we called as Sharper but the exchange is her eyes. and sometimes will possessed her and do stuff in she will.

And as we saw in the anime yumeko is a beast in gambling thats why Mary got envy as she defeat by the new student jabami.

Revelation
And as we can see to her page i mention she reveal the mastermind as in the codename of "SHE"  and base on her post we can say that this creature is powerful

Is it a trick? Real? Arg? Or just another creepypasta? Who knows"'I dont like this gambling of hers, you have one tocken and its your soul'"-full phrase from 666.yumeko. EXE