It's often said that a girl's best friend is diamonds. I think that depends on the lady, and it is not the case with me. I like diamonds, they're sparkly and expensive, although they're not my favourite gem stone and certainly not my best friends. I like things that look nice, but serve a purpose, and a for a lady in my situation my best friend is something I can use.
One of the mistresses at School Mistress Fantasy seems to be of the same opinion. Here she is showing off her's and my best friend.