Hmmm, well, hmmm. Do you have room for a larger litter box, a super high sided or hooded one, that he can stand up in and pee against instead of your wall? Brian used to pee standing up and I didn't have room for a huge litter box (which I now have) and would pee all up the wall in a box without a lid. With the lid on, he'd still pee half way up it and some pee would go between the join and still get on the wall but a lot less of it. I used to just clean the wall each time as he wasn't doing it to annoy me, he just needed to stand up. After a while, we came to an understanding about this (he was a remarkably bright chap) and he started to mostly pee in the bath when he had an extra full bladder that needed standing up and a long, forceful flow. He used to do this over the plug hole so his pee would go straight down it. I would find tell tale signs of yellow splashed on the side of the bath and shower it down, then put disinfectant down the plug hole. Not helpful for you but perhaps look into a high-sided box. It can take some cats up to a year after neutering for all the latent testosterone to leave the body. In a few (very few) cats the testosterone never leaves and so they continue to spray. The spray doesn't have the foul stench of intact tom spray though. The strays outside must be really doing his head in. Is the area outside the window yours to use? You could try growing some cat deterrent plants like lavender, rosemary, and the curry plant - all of which smell lush to humans and yuck to cats, and none are harmful. And perhaps spray the outside of the window with citrus (lemon) juice, which cats don't like either. Trapping and neutering would also be a wise move as intact stray tom cats are no good for anyone. Also, does he have a cat tree? A cat tree or shelf higher up than the outside strays can climb might make Dova feel more secure in his territory. And cats like to be high up regardless and also love looking out of windows, so a cat tree near the window would be a good idea. And, if he has his own high platform he might not jump up onto tables and counters so much. I figure that cats will go wherever they like and although I don't encourage them jumping on kitchen counters, I don't shout at them for it. I just put them on the floor, repeatedly, without making a fuss, just perhaps saying "no" once in a firm but friendly voice. Cats take a long time to "train" but will get the message eventually if done calmly and repeatedly. And, cats respond to reward rather than punishment, so hissing is perhaps not the best method as it signals distress for cats. Try just saying "no" then putting him down or in the the hallway, over and over and over again. And, when he walks passed a counter without jumping up but looks up at you, and perhaps gives you a wee "meow", then reward his good behaviour with encouraging words and soft tone of voice; and maybe even give him a treat if/when he gets to grips with not jumping up. As for aggressive playing, the best I can suggest is what you're already doing, and that is to stop what you're doing and back off completely. Hopefully he'll grow out of it. He may find something you're doing overstimulating, so doing nothing until he chills out is the best approach. Now, chomping down on bin rummage and growling is most odd, indeed. Have his teeth been checked? Maybe they hurt and he's trying to tell you. Or maybe he's guarding stuff in a territorial manner. Does he have plenty of toys strewn all over the place? I really don't know, but simply turning around without making a sound and relocating yourself away from him is the only thing I can think to try at this stage. But check his mouth and teeth out. As for stinky poos, why not try some probiotic paste or powder, the friendly bacteria will help fight the stinky unfriendly bacteria from within. Talk to your vet about it, and generally bring up the stinky poo issue as it could need veterinary attention. Also, does he have access to enough clean, fresh water? Fresh water can only help. Cats don't like to drink in the same area as they eat or go to the toilet, so move his water bowl away from these other areas. I'm glad he was howling with joy at your return. Now that he's had a test run and knows that you'll return, Christmas shouldn't be so disorientating and lonely for him. And, perhaps you'll bring him a present home, joy!