Feline ill feelings, but not from where I expected

Now that we know that Stray Girl has a clean bill of health, my husband wanted to see how our Molly reacted to another cat up close and personal. She only sees other cats at the vet's office, and she's in a "mood" there, so it hardly counts. I put the harness and leash on Stray Girl and brought her inside, which thrilled her because she definitely knows indoors - and likes it! She was sniffing and rolling on the rug when Molly came down the hall.

Molly stopped at the living room door, looking at the new cat but not particularly excited. She walked up slowly, no puffy tail or anything, and did a friendly "nose to nose" greeting, as if to say "Hi there, who are you?" My husband and I were holding our breath, because we were expecting her to throw a fit.

Stray Girl was the problem. She looked Molly in the eye and hissed, like "I'm taking over here!" Whereupon I scooped her up and took her back to the garage. I'm not having Molly terrorized or beaten up in her own house.

Perhaps next week, after the snip-snip, she won't be in the throes of hormone hell and will be friendlier. She's in season (probably the reason she was dumped) and we are going to have to listen to the "unrequited love blues" from the garage all weekend. Her routine is sleep, meow at the window, beg for food, rub ankles, sleep. Oh yes, and pull down my garage window curtain rod. Gotta fix that next week.

I hope her mood about other cats changes after she's spayed, because while we don't plan to keep her, fostering and placement would be easier without all-out feline war.