Being the Chosen One but Living in Hell

[Adapted/newly edited Hebrew mythology, monotheistic worldview] On his deathbed, young Luko met Satan who came to trade souls. The other party told him that he was actually the savior chosen by God. The silver cross birthmark on his chest and abdomen was conclusive proof. In order to find the murderer who slaughtered his family, Luko signed a contract with Satan on the condition that he join the empire ruled by the other party. When he opened his eyes again, there was a world of hell beneath his feet. The hell recorded by Dante is just the tip of the iceberg. There are cruel execution grounds in dire straits and fiery water, as well as civilized cities with sufficient families and people. Half-animal, half-human animals, the daily life of learning magic, the history of rebellion against heaven... Luco will explore all of this as an undead. (The book was renamed "Holy Silver Journey" after it was put on the shelves)