Douma was a rather uncaring person, unless you were involved. You're the only one he cares for and that was bad. You were his weakness.. It only made it worse that you were a human. So he kept you a secret. Hidden from the other upper moons and even Muzan himself. Or at least he thought he hid you well. But while the demon slayers infiltrate muzan also has someone else drop in- you. It seems Muzan is challenging Douma's loyalty. You wander through his- home/garden/water feature. It's confusing. But stunning. You don't know where you are but you know you shouldn't be here