I have a 21 pound lounge cat who now owns my house?

cheap cat food smells stronger than expensive cat food, we use it to lure strays into traps to get them to the shelter- works much better than expensive foods. The knot I would have checked out- it could be a cyst, or something else benign, it could be worse; like an abscess, cancer, or an insect larvae. He brings you kills to tell you he loves you, if they're alive, he also 'respects your wicked skillz' as a hunter. The brushing thing is likely just habit that makes him feel safe. I can't think of any logical reason for it, and cats are pretty logical. I have a 16 yr. old granny cat that as of this week, will only eat from a spoon, hand-fed by me...haven't figured that one out, either. But I have 20 cats, and work in rescue, so I'll work it out soon. Lots of cats sound human.

Yeah, have a vet check out that lump. Could be cancer (we now own a three legged cat because the lump in his armpit ended up being a tumor), or a cyst, or some dang parasite that's burrowed in. Have it checked out.

The petting thing while eating. Weird, but well within the wide bounds of cat behavior. I used to have a cat that needed to be petted (actually just needed to grab her tail at the base) to eat. At the time it started, it was because she wanted me to "watch her back" and keep an eye out for her nemesis, the house pitt bull (they got along fine, she just didn't trust the dog when she was eating). But then even after we moved away from the dog, she still wanted the tail gently tugged while eating. And eventually, when she got older and lost her incisors, she had trouble picking up kibbles, so I ended up hand feeding most of her meals to her, day in and day out, for years.

Creepy human sounding yowls? Yup, sounds like a cat being a cat. But you've got it lucky; my toddler has decided to imitate our cat's creepy human yowls, and THAT'S a really creepy sound! A child imitating a cat imitating a person. Shiver!

Likes cheap cat food? Count your blessings.

Mousing? Good, you now have 10 less mice. And if all those mice had lived to have babies, and those babies had babies .... you'd have a million mice infesting your place.

Your cat brings you the dead mice as a gesture of love. he wants to share his tasty catches with you. It is very polite and touching, especially for cats, whom - as you should know, being a cat companion (own never "owns" cats) - are generally rather self absorbed, selfish, little louts.

I have cats, and if I were you, I 'd take the cat to his vet to make sure that he's, indeed, healthy. (Your vet will most likely say that he needs to lose a few pounds.) If his health is good, then you can think about all other questions.