This has been a sad week.
Apollo was never the healthiest cat. He nearly died on multiple occasions, and at one point needed surgery to save his life. In recent years, he's had elevated kidney levels, as a result of the previous urinary issues damaging them, and questionable thyroid results. He was only 10, but sometimes had difficulty jumping and would use his claws to climb up on many things.
My mom often "joked" that he had already used up 8 of his nine lives, as she was always surprised he was still alive.
Still, he was often active and alert. He was consistently sweet, always being next to me when I was feeling ill and usually wanting pets and cuddles above all else. He was more dog-like in some of his typical behavior, as he was warm and friendly. He would never hide when not feeling well, and even at the end stayed in the living room instead of hiding. During one of his urinary incidents, I feel like he went up to me and meowed "help me!" as he seemed to understand humans could fix it, even if he was terrified the vet.
I remember when he was a kitten and used to play tag with humans by running back and forth happily.
They said he had fluid built up in his lungs which can be caused by pneumonia. It isn't 100% certain though, as there can be other causes of that. I ran She kept on reassuring me that "cats hide it really well." I would guess that, combined with the toll the past issues took on his body, he couldn't fight it off.
I took him to the regular vet a day before, and then ran a blood test on him to determine why he wasn't eating. I got a call back the next day saying the tests had too low of a yield to be read, and they needed me to bring him in to draw more blood, but by that point he had already passed. I did run him to med vet that morning, but some point between when I picked him up and when I got there, he was gone. Considering the noise he made when I picked him up and how his legs were already stiff, I almost wonder if he took his final breaths then.
He was such a lap cat that the world feels emptier, and so many tiny things feel wrong. I'm used to him waking me up every morning to try to get food earlier. I'm used to him jumping up next to me to curl up and sleep next to my pillow every night. I'm used to him sitting on my lap or trying to grab attention when I'm at the computer by walking on the keyboard.
He would often try to join in video games, and made some interesting choices during FFXIV trials and raids for me.
I wouldn't say Abra was close to him, but they got along and would often play with each other. Abra has been meowing sadly as if looking for him, and I found him sniffing the spot on my bed where he always slept.

RIP Apollo, a sweet, beautiful cat who suffered too much in this life. Hopefully he's at peace.
( Some photo spam )