I know that using a Multi-Compartment Keepsake Box on one of your pets give them at least 10 more slots for their treasure chests, but what is, like, the most slots the Multi-Compartment Keepsake Box can give?

I heard the highest amount of spaces you can get is 15, for me personal it's 13 though but I only used three of them in the past. ^^;

- Okay, thank you very much for your help! :)