I still think Uyu Hitori is likely Loki rather than Yuu.
They both do have similar manners of speaking, but Hitori's voice is slightly softer than Yuu.
Hitori listed in her debut that she hates spicy food (
timestamp), professing a love of burgers and sweet foods. She also put particular emphasis on singing and graphic design.
But Yuu stated in her debut that she likes Tabasco sauce and spicy foods, suggesting even that she'd eat spicy ramen after the debut. She put singing in her dislikes, saying Phase Kaleido has 4 great singers and she is not one of them.
I guess we'll see tonight.