There is a book held open with a rock and a wooden stake; and next to it a messenger bag; and beside these a teenage girl, painting goat blood onto the floor of a crypt.
"Okay, I will bring you something that unambiguously qualifies as coffee." And off she goes.
She comes back later with a large paper cup of black coffee, and a creamer and a sugar packet in case Ellie wants those.
Ellie will accept them graciously, and then add both creamer and sugar before she drinks.
"Thank you."
"No problem. So, since summoning does reliably work here is it a good idea for you to go home and come back with history books for me to look through...? I'd have the advantage that as long as you got anything from the right time period it's more recent for me than you."
"Yeah, fair enough. This evening I can draw out a circle for you incomplete and you can check it over and then go home overnight and I'll call you back in the morning?"
"The basics of summoning itself are relatively simple. Most formal courses include digressions about the history of the practice and background information about the daeva planes and cultures. And the essentials are repeated over a longer span of time to ensure all students have a firm grasp on them."
And when it is dark enough for Bella to break into the library she goes and does that, and she comes back with a book of simple spells for Ellie, and she draws out a summoning circle to retrieve her teacher fairy in the morning.