I am not familiar with Poser software, it looks like some 3D modeling software which is not what WireframeSketcher is for. However WireframeSketcher is not limited to website design either.
If described quickly then WireframeSketcher is there to help with with sketching and fleshing down your ideas about the UI, without going too much into the details. The UI can be of any kind. There are also specialized stencils that can help you with some specific kind of UI, be it website, mobile or desktop.
If you are looking for wireframing games then existing stencils might now help you much. However you can extend your palette by importing SVG images that are directly supported by WireframeSketcher. So you can add graphics for various characters and objects that you might need.
If you give me more details then I can try to help you more.