She is happy and playful and has very weak heats when she goes through heat and I think I finally understand why. Casper despite being fixed for a long long time now has been mounting her and doing his thing much to her delight XD Of course we don't scold them for this since that would only cause anxiety in both cats, especially Casper.
So I guess this keeps her heats in check and she has time to play, eat and just be normal in general when she goes through estrus.
BUT what do we do once she gets fixed? Those first few weeks where if a male mounts her she could die? My vet suggests giving Casper some pills that would further dull his sex drive, she says they won't affect him poorly since he is already fixed. She says males in his line are generally very sexual, his dad is like that too so it's normal for him to act this way around an intact female. Some toms do, some don't. So far, so good, Kala eats well, she finally got somewhat addicted to that one type of dry Royal Canin....you can't leave any kind of Royal Canin out tho, Casper gulps it all down in seconds, he is addicted to the brand so we feed Kala separately whenever she wants

Keeping them separate after the surgery really isn't an option with how small a place we live in, so hopefully the pills will keep Casper's sex drive in check while Kala still attracts males for a short while after being fixed.
I understand all this is very frustrating to read to those of you who get upset over cats not being spayed on time, I was the same way and still get VERY upset when people I talk to locally REFUSE to get their pets fixed, but Kala's case is a tad different so we're just trying to minimize the risk of the surgery. She should be fine now if we keep at it and she eats well until then.