why does my buddy do this?

My buddy has started to do this about 2 days ago. He goes to the front door of my apt. and just stays there. I go pick him up play with him and he just runs away and plops himself by the front door. He doesn't meow when he's there. He'll just sit there and sometime fall asleep there. When we sleep though he comes to our room and INSISTS he sleeps on our bed with us. Morning comes and I meet him at the door, just b4 I am about to leave for work. There are no other cats on the floor, of my apt. At least none that roam the hallways. And I have not seen any other pets on my floor either.

Ah....my cat has done that. My cat will not only sit at the door...he will WHINE at the door. I've just accepted that Tigger is reacting to scents that I am unaware of...and he doesn't seem to be interested in escaping...so I simply let him do what he does. That probably doesn't help your question...but I wanted to share that I have had similiar experiences with my cat.

Katie

My cat did that when I first brought her in. She had to stay isolated from my family's cats so she was stuck in a bedroom. She spent most of her time at the door even though she had kittens. I put a bed out for her close to the door but far enough so she wouldn't get hit everytime someone came in, but she wouldn't have any part of it, and chose to sleep on the hardwood floor instead where she got disturbed everytime someone had to use the door. She never meowed at the door or tried to get out. I figured she just liked to sleep there because she could smell what was happening on the other side. Plus she had kittens and was used to being outside, so she was probably watching out for the kittens as well.

Even though your cat doesn't have kittens, perhaps it could be something similar? Maybe he smelled/heard something on the other side of the door that either piqued his curiosity or a protective instinct. Do you have any other openings in your apartment such as a screened window? He could just enjoy being able to experience what's going on outside beyond the apt, even if it does seem like such a minimal way.

Dori does that. She just goes and sits at the door. She never wants to go out, and so I just let her sit there. I often wonder, why though. About 6 months ago before she got spayed she was always meowing at the door. She still never wanted to go out, but one day I came home at lunch time and found Austin, the neighbors inside/outside cat up on the 3rd floor outside my door. When he saw me he tried to gradual walk away, like he hadn't been sitting outside the door. It was kind of cute. Like when a parent comes home early and catches a boy inside the house