Dagger, child dagger, “kiddney dagger”?
 

A small dagger, engraved with initials, handle made from bone plates intertwine with brass, very nice thing.

If someone knows more about it?

You have not included a ruler/tape measure.
At first I thought such elaborate, delicate detailing might indicate a woman's piece, but it seems it is intended for outer carry (the belt loop) so I don't know.
Measurements might help.
Fine and fascinating weapon... and very effective.