Combining two fandom ideas together for some angst, but mostly amusement I promise.
The first being that Rumi is absolutely cat like. Purring, growling, grumbling all the fun things because honestly I just like that headcanon it's great.
The second being Mira with abusive parents.
Rumi who does do all the dumb cat things, including on occasion knocking shit off counters when things are quiet, but purring in contentment no matter how embarrassing she finds it, grumbling growls when she's annoyed, all of it.
But she does not ever do it around Celine.
Mira, half raised by Celine in her teen years wants to assume the best, wants to believe that Celine would absolutely never harm Rumi physically that's not the woman she knows. But she also knows that Rumi's life path is paved with harm done with nothing but the best intentions in heart.
Mira who can't help but worry about it, eventually vocally one day about how she'll be herself around Zoey and Mira, but she never makes noises or acts like that anytime Celine might see or hear her do it and how she's sure it's not entirely rational but she can't help the way her brain twists and worries over it.
Rumi obviously stalling over answering at first, face going a little red when she has to answer that yes she was sort of trained out of doing it around Celine, and other people entirely but not in the belts and slippers and angry words way Mira's thinking of.
Rumi having to admit much to her chagrin that she was mostly trained out of it by a very patient Celine who called her growling whining fits adorable and 'very scary' but "Sorry, only human girls get treats, I'm afraid. If only there was another human here to share with and not a growly little bear."
"I get why you had to make her stop doing that in public," Mira finally says when she gets to talk to Celine about it, "but you have to admit it's really cute."
"Cute. The purring might be cute, and sometimes chittering at birds of course - despite the aviary incident - but the growling."
"It's adorable, like a grumpy kitten."
"It's only adorable until she bites your new makeup assistant for using too much hairspray because it makes her nose feel sniffly and you have to test the strength of your NDAs, pay out money for damages, and hire someone new."
"Sounds like their fault for not listening to the warning growls."
"You sound exactly like the four year old that got banned from sweets for the entire Western leg of the tour."