was the first male that I was exposed to for an extended time and had wondered if the "growl" was something that the males did more than the females... And there was something "puppy" about him too! When he wasn't napping, he was always following me around right on my heels. 
I used to have a neighbor years ago when I was in an apartment with balconies and she had a female short hair (white and ginger) who was not spayed, and she would let the cat out to wander from balcony to balcony. She would visit me often and chill out by my balcony plants and was very friendly. But there was one time when she wandered down while in heat and the howling was unnerving. She even tried to get in from outside while howling, after climbing up and down the screen door. 
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