Davina Claire is a powerful harvest witch and one of the main characters of The Originals, serving as a major antagonist.
Davina was a teenage witch who was supposed to be sacrificed in the Harvest and the show's protagonist, Klaus, saw her as a weapon to used against the witches, as a result, she had been the main subject of a power struggle between the werewolves, the witches and the vampires.
Marcel had kept her and used her as a weapon against the witches, however, he was trying to protect her from the Harvest ritual, where four teenage witches had to be sacrificed so that they can be with their ancestors.
Even though she was sacrificed, it failed as she was resurrected. She now had a lust of revenge against Klaus due to him hurting her friends and using her.
She did so by resurrecting his step-father, Mikael, the vampire who hunts vampires. However, she actually puts a spell on a bracelet that will have Mikael under her spell.
Davina was arguably an anti-villainess of the show as she wants vengeance on Klaus for torturing her best friend Joshua, killing her friend Tim and multiple attempts to kill her as he viewed her a threat to his reign. Davina can also be viewed as a protagonist as most of her actions were directed towards Klaus who despite being the show's protagonist had committed numerous crimes he deserved punishment for, and Davina tried to find the means to severe Klaus from his sire line as she didn't wish to kill all the vampires who'd die with him.
While initially on hostile terms with the Mikaelson family, she ends up falling in love with the youngest member of the family, Kol (while possessing the body of a young warlock named Kaleb), when his mother Esther sent him to try and gain information from her, but found himself falling for her as well, with Davina actually helping bring out the humanity Kol lost when he became a vampire. Their romance was initially short-lived after Kol's brother, Finn (who was possessing a much more powerful warlock named Vincent) hexed with a powerful curse that caused him to die within a few days, leaving Davina heartbroken.
She began to embrace a more ruthless side while beginning a mission to resurrect Kol. She becomes regent to gain the power to bring Kol back, but was tricked by his siblings into instead resurrecting Esther in order to defeat their deranged aunt, Dhalia. She later loses her status as Regent for assassinating another witch for defying her and trying to kill her (even though she had some justification). Despite losing her status and being shunned she was able to resurrect Kol, by breaking Klaus' sire bond to create a surge of energy necessary for the spell. With this she and Kol were reunited with Kol being reborn in his true body.
Unfortunately due to earning the wrath of the ancestors, Kol was cursed during his resurrection, causing him to tragically kill the love of his life, after being freed from the curse he attempted to have Davina resurrected within a protective barrier so the Ancestors couldn't do any harm, however, Kol's siblings betrayed him so they could sacrifice Davina for a spell to stop their enemy Lucien. This causing Davina's very soul to be shredded by the same witch she had assassinated. However, Kol was able to find fragments of her soul and restored her.
Davina would help destroy the ancestral plane before it was eventually restored with Davina having control of it, the Hollow later resurrects Davina to coerce Kol into her bidding by linking their lives. After the link is broken Kol and Davina leave New Orleans to begin a new life together in California.