The Savior's Book Cafe Story in Another World is yet another isekai fantasy manga based on a light novel series. It's licensed by Seven Seas. I bought my copy new.
Review:
When Tsukina is approached by a floating orb claiming to be God, who tells her that she's been summoned to another world in order to be its savior, she says no thanks. God is somewhat taken aback, since everyone else seemed thrilled to be summoned and couldn't wait to start their new lives. However, all those other people were starry-eyed teenagers, and Tsukina is a single thirty-something with a stable job and a quiet life that she enjoys. She has no desire to fight monsters and face danger.
God tells her that this summoning in nonnegotiable, but if she'd prefer, she could live a quiet life and just be on standby in case another savior needs help. Tsukina reluctantly agrees but gets God to grant her a bunch of wishes so that she'll be as comfortable in her new world as possible.
And so begins Tsukina's life as the owner of a little book cafe in the middle of nowhere, whose first (and mostly only) customer, Il (the author's awkward shortening of his full name, Soeil), a bookish knight.