Marquis Olesya Lapidus: what pronoun should I use to describe them?

I’m currently DM of a Wildemount campaign and my players are on their way to Port Damali. The Explorer’s guide gives the name but not the preferred pronoun for the Marquis Olesya Lapidus. What pronoun should I use to describe them. She/Her is the pronoun to use. 🙂

— Matthew Mercer (@matthewmercer) March 31, 2021