イェット・トゥー・カム

One of three people called "Ghosts", that chase Scrooge and Carol for some reason. 

From url=http://en.wikipedia.org/wiki/List_of_Guilty_Crown_characters#Guilty_Crown:_Lost_Christmas.

Its true identity is revealed to be revealed to be the unborn baby between Scrooge and Carol. In the past, Scrooge and Carol were lovers and were forced to breed with each other in order for Da'ath to create hybrid race. As a result of this, Carol's womb underwent apocalypse crystallization and the baby was neither able to be born or to die, surviving in the form of a 'Void'./

From url=https://tvtropes.org/pmwiki/pmwiki.php/Characters/GuiltyCrownLostChristmasTvTropes.