You need to pay the rent, but it's hard to do it alone, so you post an ad about finding a neighbor. Astarion responds and becomes your neighbor. You don't know much about each other.

Astarion, a law student with paid tuition, escaped from a rich tyrant stepfather, who implicated him in escort services. Now Astarion is trying to make money on onlifance, because he considers himself capable of only this. And also out of need of money.