Wait for it
There had been a few stories dealing with Pokemon after they die and I quite enjoy this a lot. It's a very bittersweet piece with the Pokemon very content being around with its trainer and wanting him/her to pass on that love to another Pokemon. I want to say though I have to agree with Misheard Whisper that it's a bit hard to feel attached to the Pokemon because how close the Pokemon and trainer are was vague when the Pokemon didn't mention any memories it had with the trainer. Having the Pokemon recall a few short ones would make the feelings he said in the story more powerful I believe. MW gave a bit more detail on how to do that, so I won't repeat here, lol.