The SSS-Rank System: From Outcast To Overlord - Chapter 21: The Plan Changes.

Infernal Demon Dragon: A dog like you dare to face me in combat? Do you wish to die so much?

On an ordinary day, Lucius stumbled upon a strange, run-down shop. At first, he assumed it was abandoned—until he stepped inside.[You have entered the Universal Alchemy Store.][Congratulations! You are now the store’s owner.][Please craft your first potion.]Lucius blinked. 'What kind of joke is this?' But as if guided by an unseen force, he followed the instructions. Minutes later, his first creation was complete.[Love Potion: The drinker will fall in love with the first person they lay eyes on.]Lucius swallowed hard. 'Wait… does this actually work?'Before he could process it, the shop’s door swung open.Standing in the entrance was no ordinary customer—she was an elf. Long, pointed ears, mesmerizing green eyes, and a body sculpted by the gods. A visitor from another world.A dangerous thought crept into his mind.'Should I test it on her?'

God: I shall bestow the Saintess upon you.
Pope: W- wait a moment! This is a boy!
God: That is the Saintess.
Pope: ??????

And just like that, the Saintess was raised by the church for fifteen years without any questions asked…

- Description from Novelupdates

I was proposed to by the Final Boss.