A friend of mine, !cherigirl (https://www.deviantart.com/cherigirl) Cherigirl, did something very similar recently, and I thought it was a really good idea for a challenge.
So here it is.
Since I'm not quite as ambitious or experienced as she is, I'm only going to start off with *5* free sketches and once I've completed those, then try again for another 5 or more (depending on how long it takes!)
What I'm offering is an un-inked, un-coloured sketch something like this quality: http://www.deviantart.com/deviation/40733935/ (though it would be better if it were a single character for time constraints!) I'll need a description or sample picture of what it is that you want me