It's an Easter egg but packaged as a giant Lindor ball (the red ones). I spent a happy five minutes holding it and pretending to be a borrower while my DC (who haven't read The Borrowers) stared in bafflement and asked why I was giggling. 
Yes, I am far too old to still be getting an Easter egg from my Mum, but she enjoys giving little gifts and I would never turn down chocolate. Also yes, I am far too old to be pretending to be a borrower.