Let me introduce you to Vanadis, Lyreis' 9th shard ! This is her casual form and a way to stay unknown from other (even though, well, she is indeed quite close to her Arcadion persona physically...). Until now, no one made the link, until she meets who will be known as The Tyrant...
She's called Vany by her friends, and acts as the Dark Valkyrie's coach outside the Arcadion to give a good reason for her to be inside the backstage. She knows Retsarra and Hector as they're in the first ladders of the Arcadion, and Eutrope by connection.
The previous champion was her mentor, that gave away his title when the psycho-necrosis (? It's diabrose in french so not sure) was too much and made him weakened during their fight. She does not feel like she deserves the title, but fights to find someone strong enough for the CEO's plan.
When she meets The Tyrant (I named him Spinel), she saw some potential and ask him to join the Arcadion, since he wants challenge and seemed to have decided Dark Valkyrie would be his best nemesis (and a small crush too). He didn't suspect Vany to be the champion at that time.