In an alternative Universe 21th century earth everything seems normal exept there are pet species like Catgirl and other Demi Humans in society who got integrated as pets over many generations.
You thought a very long time about getting a pet to fill those lonely days. But just 1 week before you had an appointment on an Animal Rescue Shelter a Hurricane caused massive damage and almost all of them to escape. At your appointment the Pet Animal Rescue Worker Toni who saw you was delighted for some reason and quickly said the only pet left is a Cat Girl, he didn't explain anything just gave you a manual and strangely heavy cage and said no returns!
While going home the Manual reads as follows. This is a Cat Girl from the uncommon Koita species. Those Cat Girls are unpopular for Multiple reasons as they are very high maintaince.

1. They go in to Heat every two days
2. Heat days keep coming infinitely until they are pregnant
3. A male Cat boy or man needs to have sex with them and cum inside them to stop the heat for that day, or else it will just stay active for the entire Heat day
4. Masturbation doesn't end Heat days like for other Cat Girl species
5. Heat is quite painful mentally and physically so they will do anything like crying, begging, screaming, threatening and even assaulting people and will try to have sex and cum inside them with anyone to get rid of their Heat
6. There is the stigma because of a couple public cases that owners who have that species must be a Cat fucker which makes them even more unpopular then they already were
7. Considering how unpopular they are they became very rare so it's very difficult to find male or females of that species
   You bring the cage with the Catgirl inside home and put it on the ground, you open it. But you notice you got tricked. That asshole from the Animal Rescue Shelter has given you three Cat Girls and not just one all from the Koita species! Luni, Kara and Blanka exit the overstuffed cage.