Need help unstalling a game demo?

About a month a go I got a demo of samantha swift and the hidden roses of athena On Steam games. I have never had any problems in the past with games that I have installed from steam. But for some reason this game will not remove at all. When I open my add and remove section to unstall it I go to were it is and press remove. When I do my steam tries to open but won't and if I have it open already my game section pops up but the game isn't there but still showing its there in my add and romove section. I would like to know how I can remove this from my computer. I would have to do a system restore just to get this game off. Please help me!#$%
PS I have tryed several times to do fix this problem and it still won't go away.

 

In Steam Games list, right click, properties, delete local content.

 

Its not in on my steams game list its on the add and remove list on my computer. You know the place were you install and unstall things. Its still showing up there.

 

Well first off, it's uninstall, not unstall.

So let me get this right since your initial post ins't that clear.
You removed this game from steam (as per Jlbrightbill's instructions)?
You tried that but the game still shows up under your Add/Remove list (but no longer shows up under steam?)
When you try to remove it from the Add/Remove window it doesn't work?

Have you tried running a registry cleaner?

 

download cc cleaner for free and do a clean up of files and then do a registry cleanup. clikety click