No offense, but I don't believe that's supposed to be Eila... the Ears and tail are wrong(Eila's a Fox, not a cat) and the uniform and striker are deffinitely not Soumus.
Yeah, this was upped when the show was first starting (3 days after ep 1 aired actually), and even then I remember being really unsure. But not being aware of all the non-anime Witches that Shimada had already created (other than anabuki_tomoko), Eila was the closest so I put it down to artistic license.
Forgot about this image since then now, but in retrospect it's obviously not Eila. Replaced with 'tagme', assuming she even has a name.