I once had a kitty who was taken from her mother at 5 weeks and she was
similiar to this. Not very graceful, had no idea what the purpose of
digging in the litter was. She would first dig a cone shaped mound and
then sit on top of it to go. When finished, she would simply walk
away. Of course her long hair on her rear end took the brunt of the
episode.

She lived to be 14 and never changed. She was very cute and comicial
though! I have had some cats who bury their food when they don't like
it.