A blower is a business or person who is engaged in invoice fraud.
The general approach is to first call a target business to discuss advertising opportunities for the business and to glean useful information like the names of staff etc..
After some time has passed the blower sends an overdue invoice for advertising with a claim it was authorised by staff at the target business - they have their names so it must be true! Often there is no advertising actually placed in directories or other publications or the publications were never distributed.
If confronted a blower will often use hard sell techniques, intimidation and demands of quick payment in a hope to get payment for the non-existent advertising. The blower preys on busy workplaces where there might be some confusion, uneducated (or easily intimidated) staff and/or no clear advertising or bill payment procedure.
P.S. I only made this node so that e2 would become in some way work related. Hah! Take that employer.