Neisen

Background
Neisen, a shopkeeper, that Satou briefly becomes acquainted with when the latter is fascinated and buys the learning cards Neisen created.

Neisen would later become amazed and inspired when he finds out his unprofitable learning cards has spread to an orphanage, due to Yuri's acquaintance with Satou (as she's from the same orphanage). He then aspires to spread the learning cards across Shiga Kingdom not just in Seiryuu City.

Plot
He sold to Satou Karuta cards and a pile of papers (pile of papers for 100 goldWN 6-14), on the first view it was just a paper mostly composed of date and schedule, sometimes there are scribbles with random line and numerics drawn like spiderweb, but if it's read it vertically, shows info about biopsyWN 6-14, and the recipe about how to make blue circuit liquid, the record of a man's study about the making of holy swordWN 6-19.