I thought it was strange that the cat was so friendly towards Makuru. The name "Blood" certainly added to that feeling. So this cat is a familiar from Makuro's family. Why did it search out for her specifically? What is Makuru's mum planning? So many questions.
Thank you Hachi7 for the scanlation.
It was clearly planned, since the little girl said she's "retrieved" the familiar. My guess is the cat/familiar was sent in to spy on them by mom, to see if Makuro
really has a familiar or not, same as what wlftchtr92 said.
Didn’t expect us to see the mom this soon. Is the little girl Makuro’s younger sister? She’s a middle child? Oh no.
And her mom looks like her a whole lot, now the runaway vampire mistaking them for the same person makes a whole lot of sense.
I doubt she's Makuro's little sister. She's old enough that Makuro would have known her. They all live on an island, so most likely all the vampires know each other, except possibly ones that have left for the rest of the world a long time ago. I doubt her little sister would have been raised separately away from the island, as she'd be in a lot of danger from vampire hunters going to/from school.
I guess mom wanted to check for herself if they're actually master and underling but saw that their relationship is not quite like that.
If she could see what the cat saw you'd think Makuro starting to suck Iyone's blood, but them getting embarrassed would be enough to show they're in that kind of relationship. She should already knows that Iyone has the mark of a familiar on her neck, but I'm sure the cat saw it as well.