My favorite cat's formal name was "Fluffy The Conqueror", his common name was "Stranger" and he was the best cat I've ever had.
Many cat people know that if you need a cat one will come to you but sometimes the cat is the one who needs a human and it works the other way around. So was the case with Stranger.
My wife and I had spent the better part of 6 months looking for a house and eventually found the right one, closed on it and moved in. The morning after we moved in I opened the front door to go to work and found a scruffy looking cat sleeping on the doorstep. The cat looked up at me in surprise and I greeted him by saying "Hey stranger, who are you?" He immediately ran away but in the days and months that followed he would come back time after time.
In the summer he had a tuxedoed companion that he was never seen without until one fall day when he showed up all by himself on our deck staring out at the landscape and calling. He stayed on our deck day after day night after night for days on end, never leaving, calling for his companion but Tux never showed. Eventually I took pity on him and set out some food and water. He was scrawny and scruffy and almost blind from an eye infection that left him cross eyed but at that moment he became our spare cat and received the informal name "Stranger."
Stranger made it abundantly clear he desperately wanted to be inside the house and eventually we decided to make him an indoor cat. things were a little rocky the first few days with our older cat but Mouse is an unstoppable force and quickly became friends with Stranger.
It was obvious from the moment Stranger came into the house that he knew everything about it. He wouldn't go into the kitchen or the room we used as an office but he knew them. Eventually with the help of the neighbors we pieced together what had happened. The lady who owned the house before us had gotten him when he was a kitten. He was a Siberian Forrest cat, which is a long haired breed with low dander so they are often considered hypoallergenic. When she died and the house was foreclosed her family and boyfriend abandoned Stranger and he almost starved to death because of the eye infection.
Siberians are known for their "Dog like loyalty" and tendency to pick a human that they have an almost unnatural bond with. So as it turned out when we bought the house it came with the a cat in desperate need of a human. As it also turns out that human was me and Strangers formal name became "Fluffy The Conqueror" and I became his human. Whenever I went to work He would lie down in the last place I sat and wait until he heard my car or truck coming down the road, then jump up to meet me at the door.
He was a cat of routines and had a special one every day while I sat in the living room he would go to the door and look back and forth between me and the door. I would ask him if he heard a ninja on the other side of the door and he would get very excited. I would then go to the door and crouch down and ask him if he was ready, he would put his face close to the crack and get ready. I would then jerk open the door and the two of us would jump around it together to try to catch the ninja who often left Amazon packages. He would then shake his tail at the door, then ask to be picked up and held so he could get a better view to make sure the ninjas weren't hiding somewhere. I am going to miss those ninja checks.
Stranger was a happy, healthy, large cat, although at 18-20 pounds he was on the small side for a Siberian. He showed no sign of illness until two weeks ago when he suddenly started breathing badly. We took him to the vet and the vet said he had pneumonia. She drained his lungs and told us the fluid was not from a virus but was from something terminal and for $300 more they could tell us what but whatever it was it was incurable. I saw no point in spending the money for no other purpose than to find out what was going to kill him so I took him home. Over the next week he miraculously got better and began acting like his old self but then after 2 weeks he started acting like he didn't feel well and we weren't sure if it was his allergies or the pneumonia was coming back.
Over the past couple days I fed him his favorite foods, raw tenderloin, ham and chicken as we watched his condition slowly deteriorate. This morning he seemed pretty good, he ate, drank and used the litter box as usual but when he asked for brushing from my wife he began breathing hard. We contacted the people who make house calls to euthanize pets but the soonest they could be here was Tuesday at 11AM. We kept an eye on him throughout the day and eventually his breathing became bad again and we had to make the call that he wasn't going to make it until Tuesday so we called the vet to let them know we were bringing him down. It was a struggle loading him in his carrier, he fought and even bit me but we got him in, loaded him in the car and headed for the vet. He passed away before we got there.
Fluffy The Conqueror had finally met his match and I will miss him greatly. He was the best cat ever.
My house seems to send up a beacon to cats in need.
She has an L shaped desk and he would often lay on the right hand desk where she would rest her arm on him and pet him. A lot of time he would ask her to put youtube videos for cats on the computer so he could watch squirrels and birds and such. So whenever she sits at her desk she is constantly reminded of his absence and cries. 
