I wrote a book under a pen name, Bic.

The line is a compact pun built on the double meaning of “pen name.” Instead of referring to a pseudonym, the speaker treats it literally as the name of a pen—“Bic,” a ubiquitous brand—turning authorship into a joke about tools and identity. The humor depends on deflating the mystique of writing: the “pen name” is not an elaborate alter ego but a cheap, everyday instrument. Read more broadly, it plays with how authors construct personas and how language can mislead when idioms are taken at face value, highlighting the slipperiness between figurative and literal meanings.