We've done this style in the past and it was such a hit, we brought it back in a new color. It's made from a super-absorbant fabric that kinda looks like a towel, but feels silky soft. You won't want to stop touching it. Trust.
We put a lightweight loop terry (read: feels like a towel but a million times softer) on the outside and jersey fabric on the inside to create the softest, fuzziest shirt you'll never wanna take off.