Engagement in the act of using the language and thoughts of an unaffiliated party, under the pretense of one's own original work. Typically justified through the denial and disbelief of Copyright.
To steal from someone, claim that they improved what they stole from you in some manner, and then have the audacity to suggest that they should charge you for the rendition.
Having plagirized someone elses work, the publisher tells the copyright holder that they had to make a few corrections to the literary piece and therefore the copyright holder now owes them money for the extra work of proofing the plagirized article. The copyright holder then realizes, they have just been grigged.