The Vexations of a Shut-In Vampire Princess, Vol. 5 (light novel) by Kotei Kobayashi
Things are finally starting to settle down for Komari after her hectic trip to the Heavenly Paradise. That is until Pope Julius VI, supreme leader of the Scared Church, shows up at the entrance to Mulnite Palace one day! And if the arrival of an important geopolitical figure wasn't stressful enough, the Empress is nowhere to be found! Now it falls to Komari to tide things over with the guest of honor until someone can locate Mulnite's missing Empress...