I Had To Defeat the Demon King Using Recovery Lotion. ~Slippery Isekai Conquest Diary~ summary:
One day, high school girl Aira Hagiwara is suddenly reborn in another world as the Great Saint.
Aira is excited to be in a fantasy world just like her favorite video game, but the only skill granted to her by the goddess is a strange one: "recovery lotion".
Saving the world with lotion(?!) A slimy adventure comedy!