Echidna (real name Aena Paula) is a character from The Bouncer.
A supervisor in the Mikado Group. She is arrogant and hates to lose. She boasts a flamboyant outfit wearing black sandals and a unique hairstyle. Echidna has some sort of history with Volt.
Echidna first met Volt while he was a bodyguard for Master Mikado. Like her rival, she also soared through the ranks and became a special agent as well. However, since they were both the top dogs, she always wound up as being Volt's shadow since she seems weaker than him. Her jealousy and hatred for him was shown when she challenged him to a duel, and he refused the offer since it was unethical to lay a hand on a lady. A few years later, Master Mikado was killed. It turned out that she framed Volt for the killing after she ordered security to gun him down. Since then, he disappeared.
The Bouncer tetralogy[]
Mikado Saga[]
Echidna was first seen on Mikado's cargo train as Sion, Volt, and Kou boarded as stowaways. She challenged then to a fight, in which Kou made a misogynist comment and was shocked to see her old rival, Volt, thinking he was dead, although it's not the same Volt she knew. She and her rent-a-cop allies were defeated and vowed to see a woman's wrath next time.
She was also brought up by Volt as he explained some of his dark past to Trunks, in which he grew fascinated with. She was the one who framed Volt of Master Mikado being murdered. As well as attempting to be the top dog of Mikado since Mugetsu and PD-4 were eliminated at the moment during the rematch. She was frustrated on Volt always being a better bodyguard for Master Mikado and she can never beat him, even though he fights honorably, excepting when she was assisted by two deadly robots. Volt then urged her to leave Mikado and live a normal life, which was when she redeemed herself that the Galeos took off with Dominique inside.

Echidna at center of Character Select

Echidna with Ayame and Leann on Character Select
She then urged Volt to never die on him as he owed her a rematch as the heroes boarded the Air-Carrier. After Dauragon was killed, Echidna offered Volt to be Fate's new Bouncer.
Other sagas[]
In the other sagas, she took on a more heroic role as Fate's new Bouncer and eventually ran the place alongside Volt after Boss passed on. There wasn't a power struggle this time, and she assisted Ayame and Leann to find the brainwashed Bouncers amongst working for the neo-Yakuza and a revived Dauragon!! She fought off Volt, though the women were trapped! She then discovered of Mikado's new cloning/mind-control method, unlike the ROBOTOMY surgery of Mugetsu, by placing electric signals into the Gator Cortex of the brain which controls instinct, hunger, etc. She and the women dealt with the Biolizard twice, and eventually met up with Chiaotzu who removed the digital chips as the building was collapsing! The heroines escaped to the Lookout and awaited the Saiyans to defeat Dauragon's chimera form, then she reunited with Volt and discovered she grew very tender and was expecting! Hers and Volt bared a son named Pence and watched over Fate to this day, even assuring Ayame she shall be a mother figure to her after Ayame's family passed.