Not unreasonable. Only one person should actually have full responsibility for the two cats because what happens when you two are no longer living together? That is cruel to separate them. Tell her that. Also, they need to be microchipped, registered with the city and the vet. One person's name is going to be on there for all the contact information. It sounds like getting a cat to her is an after thought and just sounds 'nice'.

If she isn't in a financial position, you should show her how much it takes to take care of cat. I have three cats and one with a medical condition. I spend about $200 a month on food and litter for them. This is for three cats though. I took my one of my cats to get a teeth cleaning and that cost $300+ dollars. Vet require some vaccines and blood work which can be another $300+. And when they get to be senior cats the expenses go up. Then $60+ for just a vet visit. Toys, litter boxes, cleaning supplies, etc. If the cat gets sick x-rays can be thousands of dollars. I think just telling people who never had a pet before those kinds of numbers might make them think a bit more.

If she's never had a cat before maybe suggest you take full responsibility for the two cats and your roommate can help take care of them to get to know how to take care of cats since she's never had any.

Also, if you get these kittens and don't want to share, make sure they bond with you first and not your roommate.