Shadow Slave: Immortal Ice

FYI
This is a rather dark and gory fanfic with an OC in the universe of Shadow Slave(the main cast MIGHT appear but only later and won’t play a significant role)

synopsis:
Eirwen is a rich and spoiled guy who gets infected by the Nightmare Spell and gets granted Immortality and many more insane powers. Immediately in his first trial he gets tangled up in the affairs of the Underworld, a strange place located God knows where.
Eirwen gains insanely strong powers and a mysterious companion/teacher, Leviathan, whose goal is to reach the last layer of Hell through Eirwen‘s help. What are Leviathan’s goals and what will Eirwen do?