sagishi, 詐欺師 = con man (or woman, although I don't think I've ever heard anyone say "con woman" in English)
My dictionary comes up with "swindler," a word I haven't heard in a while. The last time I can remember was in elementary school when I read
The Great Brain series, in which author/narrator John D. Fitzgerald depicts life during the late 1800s as spent with the genius who was his brother, and who also used his brains to swindle folks. It sounds like the word was used often during that era.
I came across さぎし in a tv show called
Hammer Session, which is based on the manga about a Robin Hood-type con man who poses as a high school teacher and eventually changes the lives of the people he meets. He calls himself a さぎし。
There was no code for embedding the video, so far as I could tell. The url is
http://www.drama.net/m1/hammer-session-episode-1/part2
He says it at about 3:45 into the segment. There are English subtitles.
If you want to see the first episode, here are the links:
Part 1
http://www.drama.net/m1/hammer-session-episode-1/part1
Part 2
http://www.drama.net/m1/hammer-session-episode-1/part2
Part 3
http://www.drama.net/m1/hammer-session-episode-1/part3
I think it looks pretty interesting. Sometimes kind of ださい in some places, but good-hearted and entertaining, from what I've seen. I haven't seen all of it yet, though.
Couldn't find much of it on You Tube. This one is soundless; because of the copyright laws, the audio track was disabled, but it'll give you a visual taste: