Lore for Grimroses: 

Enchanted roses that serve as the most powerful thing in the Bloodlines universe, the universe in which the book I'm writing is set. Known as “The Flower of Isis.”

 They can heal any supernatural wound and/or sickness, remove any curse, sever spiritual bonds and even bring beings back from the dead. 

They power the strongest spells, curses & magical objects in existence.

They can remove and grant immortality if used in the right way.

They change color depending on the most powerful supernatural energy or emotion around them.