A weird leaves succulent

[Petitbon]

Hi everyone :

A friend bought this plant some times ago. When visiting his collection he asked me for its name.
Can anyone help me ? An idea about the family ( or even genus ) ?
I don't think it could be Crassula ovate ' hobbit ' or ' Gollum '.
Thank you.

[Aiko]

My first thought was Peperomia.

[Petitbon]

Peperomia could be a good track.
I'll trow myself into piperaceae family.
Thank you Aiko for this clue