This is one of the lead roles. So this girl is 17, but turned 18 because her birthday is on the first episode. She is the fraternal twin sister of Aether. If you don’t know who Aether is, you can check him on the Roles list. Her personality is more over intelligent and can be violently insane because she experienced the same trauma as Aether. To discover their past, you need to be on cast for the project so hopefully you can get in. You can try thinking of Niffty from Hazbin Hotel as a close version, but Luneth is more calmer. Mostly.