A wenner is a person wiht no scruples who will employ you to do a job and then after it has completed refuse to pay on the grounds that the work was unsatisfactory. At no time would this issue have been raised before. Further, the work you have done is then used in exhibitions by the person so that they can further their own career at your expense.
'I think I've been wennered', 'is this contract good, or is it going to be a wenner?', 'don't you wenner me on this'
A penis, male genitals. Derived from weiner.
shut up or I'll punch you in the wenner
This is a person who makes use of the services of a company and then refuses to pay, claiming the work done was of low quality, despite then continuing to use that work for their own self promotion.
Are you going to wenner out on us? Is this deal a good one or is it a wenner?
I can't believe we've been wennered!