The Demon Lord — Paula Altenburg

The Demon Lord has conquered the mortal world and sampled its pleasures. Now all he needs is to conquer the goddess who is meant to complete him. She, however, has other plans.

Allia is sent by her goddess sisters to win the heart of the Demon Lord and make him her slave. But Allia soon discovers that the Demon Lord's heart is not easily given, and that in order to win it, she must sacrifice her own.