It's very possible they can, since we've seen Kanchome use his own spell from an unrefined version of bottled spells, and one of the enemy partners have said they were once humans. So it's possible our human heroes can use the bottled spells, or, perhaps even pour the bottled spells into their own Spellbooks.i bet Tio's spell will come in handy.
can it be used without the book though?