Being a friendly spirit at heart, Angel tries to seek the most human traits in her best friend, a friend that she met in NESTS: the heartless Kusanagi clone, K9999. Ever since they met, Angel had a hard time trying to get through K9999, since he refused to accept the friendship of anyone, and would rather live by himself without any trouble. But Angel knew that K9999 deserved the chance of being happy, and refuses to believe that he was created just to be a mindless assassin for the NESTS. Slowly, but surely, Angel has managed to gain herself the trust and friendship of K9999, as she attempts to open the warm heart within K9999's chest.

Angel and K9999 are assigned by their superiors to team up with Foxy, a high-ranked officer of NESTS, and one of their latest biological creations, Kula Diamond, to enter the next King of Fighters tournament. As usual, K9999 hates it when he gets ordered around by Foxy and her comrade Diana. Angel tries to cheer K9999 up by claiming that he is a lot more powerful than Foxy and Diana will give credit for. But she knows that K9999 won't stand the pressure for too long. Angel makes it her duty to look over her friend so that Foxy and Kula won't try anything funny against him, may he attempt to overthrow them.

During the tournament, Angel does a precise and clean job, carrying out her duties in the best way possible. She is soon noticed as a superb newcomer, but Angel knows better. Her skills are no fluke, but instead tries to stay sharp and precise during the whole fight. Soon, the tournament draws to an end, and Angel soon receives new orders by the higher commands. He informs them to K9999, who is instantly pleased and anxious. As the winners are transported to a blimp to stage their final battle, Foxy and Kula stay behind as they watch the blimp vanish in the precious star-filled night sky. Foxy wonders what will be NESTS' next move, but as soon as she says this, she is stabbed in the back by K9999! Angel stands right behind K9999 as he gloats over the fatally wounded Foxy.

Angel informs the shocked Kula that NESTS no longer needs so many agents, so both Foxy and Kula were assigned for swift elimination! Kula vows revenge for her fallen friend, but both K9999 and Angel are ready to assault the young anti- K'. Angel teams up with K9999 to attack Kula, who proves to put up quite a fight, mostly fueled by her anger for Foxy's death. But she is soon put against the ropes by the two NESTS agents. As Angel anticipates the killing blow, renegade NESTS agent K' appears and saves Kula from K9999's attack! Angel is terribly surprised that K' is still alive, and at the same time confused that NESTS could have been eliminated so easily by their own creations. A helicopter squad flies over the scene, and Angel assumes that it's the remaining NESTS troops. Angel suggests K9999 to retreat and regroup for their next plan. K9999 doesn't seem very pleased to leave his business unfinished, but he regretfully retreats, as Angel wonders when will the moment come and K9999 will go completely out of control!

Even if she is a NESTS agent who carries out illegal orders by her superiors, Angel is not cold-hearted or blood-thirsty as one might suppose by her status. She is actually quite friendly if not met as an opponent, and acts in quite a cheerful way, always trying to spice things up. Her blazing fast speed and limber legs allow her to quickly hit the opponent in many places with a single stroke. The only known friend to K9999, Angel also begins to doubt the true purpose of her superiors at NESTS.