Yeah, circles made while he's on a summons are still around when he gets home but if he has a bunch of them again he wouldn't be able to tell which one's hers.

She could do it right after instead? She's a little concerned someone will notice it and damage it.

That's a concern even if she finishes it, if someone then breaks it before he grabs it it won't be there. He could easily get materials that won't come up easily but then the city seems likely to be annoyed with him.

It just has to take a little doing, not necessarily a lot of doing. So like, not chalk, but water-soluble paint?

He can totally do a circle in water-soluble paint. When?

She picks out a time selected for maximum audience.

He takes a summon at the right time.

It's Gerlinde in an alleyway near the square. "Hi!"

"Hi! All set?"

"Yup!"

"You have to offer me a deal."

"Oh, right. Make yourself a big circle like we talked about and I'll tell you the last book I read."

"Done!" And he does that. The binding is exquisitely legal so they will not stress out their anticipated very large audience. 

"It was A War of Lilies," she says, and dismisses him.

- and he waits -

There!

Demon!

And Gerlinde assigns him to make people stuff in exchange for being told the last book she read again, then bids him goodbye since the point is she technically doesn't need to be here while he's in his circle. Felicie can call her if he needs to go.

And Minor spreads out his wings and makes himself a little chair and sits in the middle of Luxemborg's square.

Several people think he's an art installation until Felicie is done putting up signs. ("This square is his circle!" "His summoner is nowhere to be found! Oh no, he might give you your shopping unsupervised!") Some people tentatively ask him for things.

He makes them things!!

He eventually attracts crowds. Apparently he's all over the Luxembourg Shortform feeds.

He is such a well-behaved unsupervised demon. He will make people their shopping lists and flap his wings and say if asked that he doesn't think daeva need to be accompanied.

Felicie talks politics with anybody who wants to talk politics. No, she isn't his summoner, she's a protestor. People start experimenting with how big the stuff he'll make can be. Will he make this person a shuttle? Is he willing to leave the circle and come make stuff other places? How did he get involved in this?

"I can't leave the circle, that'd be breaking the law. I don't think a shuttle here now would help the crowds any, maybe if you come back when it's less busy. I want the EU to reconsider laws about being accompanied because I want daeva treated more like other people in general."