I have a sketchbook with many, MANY platypus sketches in it. These are just two of many.

I don't feel I need to explain the second one (who hasn't pictured a Platypus riding a cat? Don't try to replicate it, though; platypi are venomous, and I doubt either would appreciate it), but the first one may be a bit too sketchy:

The tubby platypus is pinning the blame for eating all the chocolate bars on another platypus. Who is the REAL guilty party? We may never know.