簿
KanjiJLPT N1
Ledger

register, record book

Mnemonic

A violent storm tore through the archives, but the ledger made of bamboo survived intact. Crafting storm-proof bamboo ledgers was the old scribe's specialty—his records outlasted every disaster, making this specialty legendary.
Additional thoughts
Visualize a bamboo notebook sitting calmly in the eye of a howling storm while everything else is destroyed. The scribe's unique specialty is building indestructible record books from bamboo. Bamboo on top, storm and specialty below.
Quick recall
A storm-proof bamboo Ledger was the scribe's specialty.

Details

The keyword for 簿 is ledger. This kanji refers to a notebook, register, or record book used for keeping systematic written accounts. It is most commonly associated with bookkeeping and official documentation, such as accounting ledgers, membership rolls, or administrative registers where important information is formally recorded and maintained.
On'yomi