What's with the ghosts on Pokemon Diamond/Pearl?

In old chateux (or however it is really spelt...) in Eterna forest, I talked to Gardenia outside, and when I entered, I went to the dining room (With the big long table) and I saw a man at the other side of it. I thought he might come over and ask for help or something, like in other parts of the game, but he didn't. His sprite went to the left of the screen, but his legs didn't move. He was a gohst in the game. I was wondering...are there any more gohsts in this house, or anywhere else in Sinnoh? Also, is there a reason for them? Like some sort of long mystery about them that only you can solve? That stuff would happen in a typical game wouldn't it? Then again, it could just be a little thing to make the game look even better!

Please don't answer with links to websites please because I never give them best answers because it dosn't actually answer the question.
What's with the ghosts on Pokemon Diamond/Pearl?
yes they are ghost there,there is also a ghost up stairs its a little girl in one of the rooms,if you have obtained the national dex you can get a pokemon that looks like a light bulb its name its rotom,an electric/ghost pokemon you can find upstairs while clicking "A" at the tv screen,it is easy to get it is a level 15 :D
Reply:yes..unlike WHAT other people said....

THAT "GHOST" did occur...





however....



the ghost just SETS the MOOD of the place...%26gt;THATS ALL...





NO ..there are NO OTHER GHOST in the game other than DARKRYIA.....and the guy in the hotel which sends you to FULL MOON ISLANDS...thats the only OTHER "GHOST " in the game..





NO...there is NO story on the ghost...%26gt;AGAIN..they just set the mood of the place ...ok...
Reply:i saw it once, but never really thought about it much. It doesnt appear in the game afterwards though.
Reply:....That man thing you saw was never supposed to happen. I've been to the Old Chateau and nothing was odd there.
Reply:the Tv screen has a Rotom in it.
Reply:It is not a glitch, but also it does not accomplish anything if you see him. The Old Chaxeux is just haunted by ghosts, and is hwere you can catch the Electric-ghost Rotom in a TV so he ghost, which quite a few people around the internet have asked about and claimed to have seen is just a way to add an effect-it is a haunted mansion.



Hope i helped.
Reply:If you have the National Dex There you can obtain Rotom (Ghost/Electric) you probably know that...um there are ghost pokemon so yes there is a possibility of a ghost.In my opinion it's a thing to make the game look better I have been to the dining room but have never seen actually a ghost.I don't know what nintendo has created but you should keep trying and maybe you'll find a way to catch a legend or something (I mean like Darkrai,Arceus).One more thing,keep going to that house over and over again you should try it because I told you .One more thing did you just went after him or did this appear ! ? If that ! then It's sure that it is part of the game