He sits by the outside door all the time.

A touch of back story the last cat I had lived roughly 20 years and we had been close companions since I was a child. He died due to old age a few years ago and I haven't gotten another one since him. But recently I moved out with some friends and they have two cats of their own, (Both of which don't like me very much) but the deal was if and when I found a cat, I would be permitted to have one.

A few weeks ago a stray wandered up to the door of my apartment and loving how sweet and friendly he was, I let him in. I've never met a stray so friendly, so I asked around in the surrounding neighborhoods and no one was missing a cat. So I've adopted this beautiful boy as my own and he will be an indoor cat since that's all I've ever owned. (I'm paranoid about my babies leaving and never returning).

That being said, he has meshed into our home quite well. He gets along with our cats, uses the litter box and is an all around lovey boy. Something I missed greatly from my last baby.

My concern is that recently I'll see him sitting next to the door on the outside. Like he wants to go out. But he uses the litter box just fine and I keep it very clean. If he were wanting exercise, I've got just about every toy under the sun and he has no interest in them. I just assumed he was a cat that didn't care about playing.

I'm not sure what to do, and I can't tell if there's something wrong with him, and my family's never taken pets to vets on regular basis unless something starts to look a bit off. I haven't had Flynn for long, so I can't fully tell what is abnormal yet. I do still plan to take him to the vet to have him properly bathed and to make sure he's treated for heart worms. I just want to make sure that I'm not just getting a paranoid bug in my ear and have to let go of the first cat that's affectionate towards me in what feels like forever.

I think he is just used to being out, so he's atiently waiting for you to let him go out again.  Maybe he even had another home and he might have been splitting his affection between you and another home, so he wants to go check in.  My neighbor and I share a couple of cats that way, cats that used to belong to a neighbor across the street who was killed in an ATV accident.  They showed up at each of our houses and were eating at each of our houses.  I took the tamest one in to be neutered and then I kept him inside for a week so he could heal.  The neighbor finallly called me asking if Ihad seen a grey and white tuxedo, and that's when we found out he was sharing himself with both of us.  Two more siblings showed up, and he paid to get the other male neutered.  When the weather was bad, I let them sleep inside in my study, but they did always want to go out again.  Now that it's warm, they are obviously sharing us again.  Maybe you could harness train your cat and then see where he goes when you go out together.

I think he's just used to being outside too. It's harder for a cat who used to go out to forget about the outdoors than one who has never been out. Mine are indoor cats but I have an enclosure outside and my indoor only male will sit at the back door and yowl quite loudly when he wants outside time. He doesn't like to play much either. The ONLY thing that interests him is 2 long shoelaces, tied together and dragged at high speed up and down the hallway (oh well, at least I get my cardio in every day I suppose). I've bought so many toys and he ignores them all, but the shoelace comes out and he's ready! I agree, leash training him might be a good option. Are you sure he was a stray? Perhaps he just went wandering and got lost?

You've already asked around and checked to make sure he wasn't a stray, so you've done your job there.  If you can leash train him, do so.  If not, he can just enjoy the great outdoors from his cozy little spot by the window!

I'm like you - I think cats are much safer inside.  Your previous cat didn't live to be 20 for no reason!

If in the future, you have the means, build him a catio.  So glad he found you!

Do you know if this kitty has been neutered? Taking him to the vet is a great idea. If he hasn't been neutered, that should be the next step, because if he's not neutered, every time there's a female in heat anywhere in your area, he'll be looking to go outside. I don't know that vets bathe cats, is there a reason he needs to be bathed? There are cleansing cloths you can purchase for cats that don't require submersion into water. Also, since he's been outside, you may want to get him a dose of Frontline Plus to get rid of any fleas. You can purchase them on ebay or Amazon for about a quarter of the price at a vet's office.

If Flynn were unhappy or truly wanted to get out, he would be meowing quite a bit at the door and letting you know about it. One of my cats was formerly an outdoor cat, and he definitely lets me know when he wants to go outside. I trained him to go out on a harness and lead, which has been our compromise.  I've posted the picture of him on his harness so many times on this forum that I hesitate to post it again because I don't want people to get tired of seeing it, lol. I can let you know how I did it if you're interested.

I wouldn't worry about him having a second home somewhere. If someone wanted him back, they would be posting pictures of him in your  neighborhood and social media. Within a few months, he'll forget about any past home and fully embrace your home. 

Thanks so much for the advice! And He doesn't make much noise, there's also tile there, being a long hair it might just be cooler for him. I'm starting to just worry about him getting hit by the door and getting injured.

I have taken him to be neutered and when I first brought him in I gave him a dose of de-wormer and will be giving him the second dose tomorrow. The vet said he's fit as a fiddle so I don't have to worry about him there.

I may try harness training him and I've recently discovered he likes playing with strings tied to balloons! At least the other toys I bought haven't gone to waste as Proxi has promptly found and destroyed them with glee.

And I have tried using kitty wipes and shedding brushes to cut the edge, but I think he used to be good friends with the dumpster so he smells pretty ripe. I haven't put him in the tub yet, and he's so mellow he might not mind, but I'm taking baby steps with him

If you harness train him, be sure and get one that fits snugly on him so he can't get out of it. My Sonny had managed to Houdini himself out of it a few times at first, but luckily just sat in the grass and didn't go anywhere. He's gained some weight since then, so that hasn't happened in a while. I also connected two leads together to get one super long one, so when he takes off into a run, I can run behind him and give him plenty of room, and also have a lot of room when he climbs the apple blossom tree. Some people try to train their cat to get used to the harness inside the house, but I've found this hasn't worked as well as just taking the cat outside on the harness and lead. They only get frustrated having the harness on while inside, but if they associate the harness with getting to go outside, they quickly accept it on their body, forget about it, and learn to move around with it. Also, don't expect the cat to walk beside you like a dog. There's usually a dot of dawdling around, eating grass, sitting down, running in spurts. My cat does sometimes walk on it, but likes to let me know he's still in control, lol.