In Lyra's system, to sell a call you must collateralize it with the underlying asset. This turns every call sale into what's known as a covered call. A covered call differs from a 'naked short' call, where the option is partially collateralized by cash (and not the underlying asset). To write a covered call the writer must first purchase the underlying asset, which means they are long the asset itself. The accompanying short call position offsets this somewhat, but unless the call is 100 delta, the option seller remains net long the underlying asset (whereas they would be net short with a short call position).