101Leafy researched the game with the Hilltop Works fan translation patch, English translation by Cargodin
Pen Stand筆壇

Pen Stand is row 24 of the game's guilü table, with the element Tree. The battle screen reads (Shoot Metal!): it is weak to Metal.
It is on drop table 1, whose first weight gives all 64 rolls to nothing, so it never drops anything even though the table lists Shellfish Powder, Guilü Balls, and Men's Extract after it.
Guilü table: Eyeball Root Pen Stand Meat Hook
English translations by Cargodin for Hilltop Works Fan Translation Patch: https://www.patreon.com/hilltopworks/posts/kowloons-gate-160555525?collection=18503