So apparently today is National Tea Day, so I sketched up this idea that I'm going to auction off as a YCH (your character here).
There will be tiers to the bidding, but the basics will be flat colour, with semi translucent mug showing the character inside the mug.
Character can be any species, although depicted as a feline for the example.

Bidding starts at $5 with $1 min increment.
30 min snipe protection on final bids.
Auction will run until 30th April; 11pm BST (3pm PST / 6pm EST)

Tiers;;
$50 - Include shading
$100 - Includes a free A4 print of the artwork, with free worldwide postage.
$150 - Get this made into a 3.5" acrylic charm on a keychain, with free worldwide postage.