Betrayed by the World, I Became an Undying Tyrant

[Western Fantasy + Gender-Bender + Multiple Love Interests + Immortal + Feel-Good Story]

After his mother dies, Eilis, the sole heir to his family, is betrayed by his half-brother to a group of cultists and nailed to an altar to be drained of his blood.

At the brink of death, the wrathful Sin Goddess Aljena makes a pact with him. Though he becomes a girl, he gains the power to take revenge and an immortal, indestructible body.

His only drawback is that he inherits Aljena's Original Sin of Wrath. The slightest grievance sends him into an uncontrollable rage, and he turns against everyone, even his own family.

Then just don't let him suffer any grievances, right?

Those who bully me get beaten! Those who betray me die!

"Miss, I know the bread I baked was a little too dry, but surely that's not a crime punishable by death."