From Villainess to Healer: Volume 3 - Ascension of the Holy Maiden, Part One

When Charlotte Cocoriara’s engagement was broken, she regained game knowledge of a fantasy world and decided to use her unique insights to become Sharon, an adventurer and Healer. Alchemist Tarte and Sharon’s apprentice rescue Pope Tithia, who is on the run from a mutinous cardinal who took over the cathedral in Zille. Determined to help Tithia win back the church, Sharon works hard to grind the levels of her entire party. When she discovers that the cardinal is trying to summon L’lyeh, Goddess of Darkness, she ventures into the Abbey to thwart his attempt once and for all.

[From J-Novel Club]