Ruska

A young boy who has spent his entire life labouring in his village on a layer of the Vertical World. Hardworking and earnest, Ruska is plauged by an insatiable desire to know what lies at the bottom of his world. After witnessing a fallen maiden (Omega) fall through his layer, takes a chance and plunges in headfirst after her. Sending him on a joruney that will reveal to him the truth of his and his world's existence. [Spoiler] It is revealed later on that Ruska is an Earthling from outside the Vertical World's universe, who escaped from a doomed planet Earth on-board a colony spaceship. Noticing an abnormality during the construction of the Vertical World, he ventured inside to investigate, but ended up losing all memory of his prior life as a consequence. [/Spoiler]