Not sure what I expected going into this, but now I'm getting strong "Otome Game no Heroine de Saikyou Survival" vibes with a young murderhobo female lead. She's probably not going on a solo assassin adventure like Aria, but I can imagine she'll live life with a similar mindset.
Her mother Amaryllis doesn't seem ready for motherhood with her naive and immature take on her daughter's act of self-defense, indications that she lived an excessively sheltered and spoiled life. A womanchild or whatever the female equivalent of manchild is.
She adopted a random girl off the streets without her husband's knowledge and agreement, and now he comes back forced to take under his wing a new daughter, a stranger who isn't his or his wife's blood-related child.
I thought Rosemary might've been an interesting little sister, but the more I saw her the more I felt like she is going to become a manipulative antagonist in Serena's life, siding with her actual mother.