This piece belonged to Mertolla, she was bitten by a vampire when she was 14. She wasn't killed by the bite, but she was transformed into a vampire herself. The "precious bite" as she called it granted her unbelievable abilities that she found phenomenal.
She used this pendant to perform ritualism of mind control. With this power, one is able to steal, create, and remove memories from a subject. You will capture their mind without them even being aware of it. This is an amazing power that you can use for your benefit. You cannot wipe out someones internal memory; however you can slightly altar someones memory.
There are so many ways to use this piece. If you've ever made a bad first impression, now you can change that. If you are a lawyer or in a lawsuit, you could sway the judge or jury to your point of view.
Use this power with caution and make sure to wear this piece for 2 weeks to embody the power that Mertolla left within it.