Mona. Groundhog Day with a Demon

Summoning a demon. It's absurd and unbelievable — even more so. This was something that old wizards and witches, who had experience in conducting rituals, struggled to achieve, and besides, it's extremely illegal. Who would dare to publish the actual... summoning formula? Nevertheless, Mona discovered it in a museum, where she works as a witch-curator. And when she needed help to protect herself from armed robbers and a vampire mage, she performed the ritual. Incorrectly. She summoned the charming and arrogant archdemon Balthazar, who is now forced to come to her aid every time she gets into some trouble. However, soon Mona realizes that the demon appearing out of nowhere and easily flirting with her is far from the most serious problem in her life.