Who is Lissa Dragomir from Shadow Kiss and what is their importance?

Lissa Dragomir from Shadow Kiss is Rose's best friend and the last surviving Moroi royalty. The current Queen, Tatiana, has plans for Lissa, some of which involve living at the royal court and marrying her nephew. Lissa has been able to practice a type of magic long thought gone from the world. This makes her valuable and it also threatens their government as they try to decide how to handle her Part of what makes her so powerful is her bond with Rose who is able to drain the spirit magic off of her when it threatens to drive her insane. This makes Lissa, and moreso Rose, targets by those who would seek to control Lissa's powers.