Can anyone tell me what an imposer is?
One who imposes.
imposetransitive verb
1 a: to establish or apply by authority <impose a tax> <impose new restrictions> <impose penalties>
b: to establish or bring about as if by force <those limits imposed by our own inadequacies — C. H. Plimpton>
2 a: place, set
b: to arrange (as pages) in the proper order for printing
3: pass off <impose fake antiques on the public>
4: to force into the company or on the attention of another <impose oneself on others>intransitive verb: to take unwarranted advantage of something <imposed on his good nature>