Why would a cat attack someone?
I have two female cats. Neither of them are aggressive at ALL, and only one of them attacks his armpits occasionally. If he's laying on the bed, sometimes she will come over and start playing and biting his shirt. She's actually bitten (playing) one of his nipples before too. It's like she likes his scent.
Both cats will also rub all over his shirts and sweatshirts with their faces and bodies and kick them with their back feet. They do NOT do any of this with me or my clothes but they do cuddle with me and sleep right next to me and on my legs/chest almost every night.
It's not aggressive behavior, it's like she gets so overstimulated that she forgets what's going on. If he moves too fast to get up she will jump up and hiss, which she seriously never does any other time.
Also- she will only jump up and hiss at him during these "episodes" where she is overly stimulated by his armpits, lol.