Still not the context I heard it used in.
When I began teaching I tried a technique a teacher used on my class. I stood in front of the class pretending to be totally oblivious to what was going on, spoke in a monotone, kept a poker face and had a permanent smile. The object was to see who the instigators are, which kids start misbehaving once others do and which kids will never misbehave.
Almost immediately I started hearing comments like “OMG, this guy is such a Harry”.
This worked until some students who had older brothers or uncles who knew me figured out that I wasn’t as innocent as they thought.
Recently I started getting harrassing phone calls from a collection agency asking for Harry Pepper and I was wondering if a student got a credit card or something in that name and gave my address.
(I finally got through to an operator who was willing to talk like a gentleman and determined that it probably wasn’t a prank. He also gave me enough info to figure out who the real Harry is- although I never reported him to the collection agency.)
In any case, once I saw this topic I thought some one may be able to shed some light on what a “Harry” is.