Erinyes is a black diva that Tsubame's Petit-Ange has been transformed and it's the fifth and final diva to be awaken after the four divas, Aphrodite, Hestia, Athena and Amphitrite. She appears in the last part of Ep 12: The Black Diva where she saves the girls from Jun, Miyama and Hatoko in their apostolus suits under Takashi's orders after they incapacitate their divas. The girls however mistakes her as Aphrodite (Hibari's Densuke).
Erinyes resembles Tsubame with medium length light pink hair and a long layered hair in each side of her hair and pink eyes. She wears a pink and yellow armor leotard under a black turtleneck suit, pink-bladed wristbands with a yellow gem in the center, pink and yellow pauldrons on her shoulders, and pink, purple and black armor boots. She also has a pink and purple helmet with a yellow face protector to protect her face and black feathered wings from her back.
When fusing with Tsubame during Episode 21, her appearance has minor changes and she resembles a black version of Aphrodite. Her armor leotard is now pink and green, her shoulder pauldrons are now yellow, her pink-bladed wristbands does not have a yellow gem in each sides of the blades, her armor boots are now pink and purple and her wings are now purple instead of black.
In the OVA version, she retains her appearance in the anime series.
Unlike the four divas, Erinyes is able to incapacitate multiple divas at once as it demonstrates this ability to incapacitate Jun, Miyama and Hatoko's apostolus suits as well as she nearly destroys fellow divas under Tsubame's command due to her alliance with Takashi which the trio were unaware of their crush's intentions. She also incapacitates Aphrodite in a severe damage to make Hibari fuse with Aphrodite by Astral Fusion. She also shown to have superhuman strength during Episode 19 where she carries four people after they been defeated by Hibari in her advanced diva state. Later before she fuses with Tsubame, Erinyes has a high durability when she tries to block most of Hisho and her diva armies' rapid fire making Tsubame's chance to tell the other girls to summoned their divas before she was knocked off the ground and Erinyes is badly damaged soon when Tsubame has her chance to fuse.
When she was fused with Tsubame, she is fast and agile like Aphrodite when she fuses with Hibari and she is shown to knock a single diva on the ground and later incapacitates them with her pink blades from her wristband which is glowing in pink during execution and is equally matched against Hisho as Diva Hakuya during Episode 24.
She has only one transformation sequence was to fuse with Tsubame by Astral Fusion and Petit-Ange is rarely shown to have transformation sequence which it quickly transforms into a diva off-screen.
When fusing with Tsubame, she was seen in a multi-colored light where Erinyes is shown to be fuse with her. She was shown in a darkness visible where it removes her uniform and her ponytails on her hair and earrings are now broken to pieces and her medium length hair flows freely and it lengthens her hair into long back-length. It forms her black turtleneck suit and her red head protector, her yellow shoulder pauldrons, her pink and green armored leotard and pink and purple armored boots. It also forms her pink-bladed wristbands in a yellow light and also forms her wings on her back which is purple instead of black and her face is shown forming her pink and purple helmet with a yellow face protector and goes in a final pose in an elegant manner.