Mosketch embeds several characters for testing purposes only. 

The following notice applies to all of them:

"Copyright ©2018 by Olivier Barbeau

All rights reserved. No part of these characters may be reused, reproduced, distributed, or transmitted in any form or by any means without the prior written permission of Moka Studio, except in the form of pictures, images and videos."

Those characters may be found in MOSK and FBX format in the following directory:

Mac OSX & Windows

<Installation directory>\Data\Characters