honey trapper
n.— «Martinez is a “honey trapper”—or as he likes to call himself, an “integrity tester”—one of a growing team of private detectives who are hired by wives, husbands or partners to test the loyalty of their loved ones.» —“Private eye defends integrity of ‘honey trapping’” by Kate Kelland in London, United Kingdom Reuters Feb. 13, 2008. (source: Double-Tongued Dictionary)