She and I had 2 cats shortly after we started living together in our early 20s. A " friend " gave her 2 cute sister kittens and who was I to object about 2 cats in a 2 bedroom apt? I did try 
we were on the second floor w outside steps to the balcony/front and back doors......... about a year later a feral tomcat found out we had 2 young, unspayed pussycats who were never let outside. The apartment was the last one on the street and big woods all around. It started w the tomcat spraying on the front door now and then, always in the middle of the night, never saw the culprit or any loose cat around the apartment. I tried hard to find or see it in the daylight for a month and more, to no avail. One late summer/fall night w the front window open and one of our girls lounging on the sill the tom jumped on the screen and started a fight w Sasha and tore holes in the screen before I could stop it. The tom left in a hurry when I opened the door beside the window, the first time I ever saw the sneaky sob........... Now the tom was spraying the front door about every night, I had washed it many times before this and NOW it was spraying the new screen/window too. Now I was really mad. I thought about trying to trap it, but worried about someone finding and taking my havahart and the weird neighbors. I had kept a wrist rocket in the den w a few musket balls for weeks before the screen incident. A few weeks later, one afternoon I saw the sob slinking out of the woods out back and towards the end of the building making it's way to the front. I went out on the front balcony and waited. The tom came around the corner of the building, stopped and looked right up @ me. I let the lead fly about 40' and hit it square in the ribs. The .50 cal. lead ball folded him up and drove him 5', it's nose smacked his butt hole w the impact. It streaked off back into the woods to never be seen ..........or smelled again.
