The Eastern Quarter's Mana Series by Dorian Valentine

After stumbling from the blood soaked catacombs, Prince Ortherion discovers he's lost more than just his memories. His father is gone, leaving the kingdom crumbling, and his rightful crown has been given to his brother. Even his lover has abandoned him.While finding a deeply needed companionship with his guard, Ortherion works to heal and piece together his broken memory and kingdom, amending what his father has destroyed... moreAfter stumbling from the blood soaked catacombs, Prince Ortherion discovers he's lost more than just his memories. His father is gone, leaving the kingdom crumbling, and his rightful crown has been given to his brother. Even his lover has abandoned him.While finding a deeply needed companionship with his guard, Ortherion works to heal and piece together his broken memory and kingdom, amending what his father has destroyed. But a horrifying creature has other plans, whispering warnings and threats, refusing to leave the prince alone. Ortherion has every bit of trust in his new guards to protect him from this threat, but the treachery runs deeper than he knows, and the past refuses to be forgotten. less

When a ritual to restore Mana goes wrong and sends him into the distant past, Célestin Edevane seeks the help of a strange man inhabiting an even stranger estate in order to prevent the calamity that destroyed Mana. Faced with a fascinating world unlike his own, filled with vampires, fae, witches and old gods and an unexpected love affair...will he even want to return to his time?