You have been blessed with the marking of the Provider of Friends. That the cat understands that he can trust to wait around you and then you'll bring a friend for him!
I wish my cats would be more chill about the outdoor cats in our neighborhood. Instead, our cats do that howling thing and get really agitated, puffy tail, the whole 9 when they see their nemesis'. (There are multiple of them)
When my family adopted a street cat she liked to sit in the window and still keep a lookout on the neighborhood. We tried to let her outside, but she made it very clear she liked living with us pretty fast. A few times some rough looking cats would just run up in our yard or porch and start howling to her. She would see them and run away. Some street kitties just like the inside.
