[Usually, she would tell the panicking girl to just keep it a secret, but now...]

Look, kid, why don't you wait until everybody's back in their normal bodies until you tell them. Just say that it was all Lancer's fault. And tell them that "Lancer" is a tall guy with blue hair in a ponytail and red eyes because that's what I usually look like.

And if any of them have any issues with you, I'll explain to them how it's my fault, so I'm taking responsibility.