The chair is weird looking but it may be based on a real one that looks just as weird.  The seat part looks about the correct height, anyhow.  The pose does look really odd, though; I just bet anyone posed like that couldn't stay in that position for long without discomfort.

Edited to add: I almost agree with Blackhearted.  The "almost" part is the use of IK, which can frequently make the knees bend left and right in exactly the way they don't.  There are a lot of poses like that for sale, too; elbows and knees moving left and right.  There's a very limited amount of left/right movement on either of those joints and it's usually because there's some weight applied.  In theory, they should only be able to bend forward (elbows) and back (knees).  And while we're at it, there are numerous hand poses with twist applied to fingers or left/right movement after the first joint.  Bleah. 

Coppula eam se non posit acceptera jocularum.

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