Okay, I had a couple of ideas for plotting and such.
Medusa is going to need new clothes, considering the only clothing she has is what she's wearing. She'll be unsure how or what to request in the provided way (shopping list), and it is unlikely she'll tell anyone until she finally needs to clean her clothes, and kind of nervously mutters that she doesn't have anything to change into.
Other ideas: her reading poetry aloud to Malkuth every now and then, in the library or west porch, or bringing him tea in the drawing room. She might ask one day, kind of offhandedly about musical instruments, and Malkuth arranges for lessons.
Medusa having a nightmare and waking up panting, before going to 'stand' on the balcony because she can't sleep, and Zeph spots her when heading to the washroom, and bonding commences.
I'm also thinking about eventually having her cut her hair, because the snakes can be too much of a hassle, and when a master forcefully cut her hair so she had bangs, the snakes didn't grow back with the hair.
Also, is Malkuth going to have guests or parties at the Manor? It might be interesting to see how he treats the girls with other people present.