The Saint's Magic Power is Omnipotent manga volume 4 features story by Yuka Tachibana and art by Fujiazuki.

Sei thought she was summoned to another world completely by accident—a bystander, a leftover, and most certainly not the Holy Saint of legends. After a short struggle, she’d finally found a happy place for herself as a potionmaker and enchanter. But thanks to her literally miraculous powers, no one can deny that Sei really is the mystical savior the world’s been waiting for.

Now there’s a whole new struggle, first to hone her powers underneath the boyishly handsome Grand Magus Drewes, and then to navigate the political consequences of her saintly power. What will become of the lovestruck prince who foolishly backed Sei’s rival Aira, or the poor girl herself, after failing to live up to everyone’s expectations?