MTL - Hao is Also a Kind of Life - ~ One hundred and sixty six:

When Su Jiu dies on her eighteenth birthday, she transmigrates into a novel about painful love and becomes an adorable four-year-old child.

[The Demon King is Dead], a story in which the Demon King got immediately killed in the Prologue. I became the ‘Demon Prince’ of said novel.

…Help me.

The thousand-year-old Imperium is crumbling, and war looms on the horizon, bringing with it both brutalities and splendor. Caught in the midst of this chaos is Lansius, an office grunt and veteran MMO player who has been transformed into a medieval peasant. With no wealth, status, or magical abilities, and armed only with his basic knowledge of the art of war, can he endure and thrive in this realistic medieval fantasy realm?Follow Lansius as he moves from one occupation to another, striving to survive during these turbulent times.

Offered as a bride to Hades at the age of eighteen.

Pestered by evil spirits in the day, and taken advantage of by a perverted demon at night.

Pervert: “Dear, a night with you is worth more than gold.”

I leaned away as I clenched my teeth angrily: “Worth my foot!”

- Description from Novelupdates