Getting a new 2nd cat tomorrow.

So we finally found a second cat that my girlfriend and i both liked, and we had to pick it right away or it would be going somewhere else. I currently have a 6 months old male cat that is getting neutered in a week. this new cat is also a male, 4 1/2 months old, and will be getting neutered on the same date as the other cat (if we can get an appointment).

As both cats are males and they are not yet fixed, but still young, what is the best way to introduce them to each other without any conflicts of violence or of territorial markings?

Cat is coming tomorrow, so i would appreciate any help as soon as possible!

both cats are officially getting fixed next monday. at that time it will have been 8 days that the new cat has been isolated in the other room. from that point, how fast should i allow myself to make switches between towels and toys, because i would like the cats to be fully recovered before meeting. or is it better to leave them roam around right after the fixing, as they will both be weak and may get used to each other in that mood?

im asking a lot of questions, but im just trying to find the best thing to do, without rushing too much although i am envying both of them to be friends...

I have been attempting a few things here and there in the last 3 days I have had them. To begin with, the new cat is very vocally lonely. So my older cat is often roaming around the door when this happens. Very often they will exchange paw swaps from under the door (the little they can reach) but im not sure if this is an aggressive behavior or not. On occasions my older cat will be on his back and rolling around while doing this, so i assume he is playing. However what I will explain next leads me to question this behavior.

On the 2nd day, I attempted to rush things a little. I exchanged blankets. The new cat seemed to pay no attention to the older cats blanket in his room, but the older cat seemed to avoid the new cats blanket as much as possible. I even put treats on it, and it took him a while before finally getting them, and after they were eaten, he stayed away from it.

Later that night, while my girlfriend was over, we wanted to see what would happen if they would meet. At first my older cat was a bit cautious of approaching him, but as soon as the new cat started to wander off, my new cat ran after him and smelled his behind. This was followed a loud hiss, which he are unsure from which cat it came, and right away i put the new cat back in the room.

On three occasions now I have allowed the new cat to roam the house a little, to get used to the other rooms, while i locked my older cat away in my own room, in which he spends most of his time anyway. I closed the room where my older cats litter is, just to not have any mixing of urine. Upon the first roaming, the new cat walked by the food bowls, and gave a hiss (this is the same spot where the previously mentioned hiss happened, perhaps it has something to do with it) but he was alone this time. My older cat would get very uneasy while in the room alone, so i limit the time i allow the new kitty out. Now this is where it gets rough... When i let my old cat back out, he proceeds to attacking the newer cat from under the door, and on the first time let out a loud sort of violent meow.

Currently they are "going at it" under the door, as i just tried it again. Even when i spend time in the closed room with the new cat, my older cat meows from behind the door.

The operation is in another 5 days. Am I doing anything wrong? Or do I have to ignore this behavior? Im thinking about trying to spend the night with the new cat, as i feel i dont spend enough time with him, but i wouldnt want to make my older cat any more jealous than he seems to be.

update since my above post last night.

this morning the new cat wanted to come out so bad, i decided to try a meeting again. at first it was much less aggressive, and my older cat just vigorously following the new one around, at occasions exchanging paw swaps. at this point i wasnt sure if it was playing or fighting, but their ears werent down.

after maybe 10 minutes, the newer cat started eating my older cats food. after this, my older cat seemed quiet, but i think he was only planning. he jumped he a couple of times, each time the new cat rolled on his back, with his ears down, i guess he was showing defeat. at every occurrence of these little attacks, i just yelled out my older cats name, at which point he backed off. and from there on, whenever he felt the desire to jump him again, he looked to see where i was before he proceeded in his plan.

about halfway in this meeting, i took each cat and cut its claws, just in case anything was to happen. about a half hour into the meeting, they were simply going at it too often, though they were not making any noises initially while fighting, at the end my older cat was breathing heavily, and thats when i brought the new kitty back in his room.

from reading around this seems like normal behavior. should i keep doing these small time meetings a few times a day or what? is my older cat just being a bully?

They seem to be great friends already, just after 2 days! The only thing however is that when they wrestle, my older cat bites the newer cat too hard once in a while and wont let go of him until we interfere. what warns us that this is happening is when the new cat whines or weeps or makes hurting noises. but even after we separate them, a minute later they are back to playing together. they are constantly together and are practically inseparable, like best friends.

do we need to stop this behavior? and if so how do we do so?