Zeke the Sneak is an agent with F.I.N.K.
That acronym stands for the Fiendish Intelligence Network of Kids. It is not really much of an organization; even Zeke as its founder and first member is honest enough (which for Zeke is out of the ordinary) to tell us it was a "gang of teen spies" which he started while in high school. From the little information we have of it, though, it is likely comprised of just five members, each one a winner when it comes to being a loser.
By the appellation given above for Zeke, i.e., 'the Sneak', you can gather that we do not have a last name for this fellow. I am sure he has one but it is never told us. Well, at one time a client for Zeke's services does attract his attention with, "Hey, Ratfink!" but is it likely that is more of an observation than an actual surname.
Our first encounter with him, and we are pleased to report there are not many of those, he is monitoring a bug he put outside a young lady's window to eavesdrop on an upcoming date, all to sell that schedule to her rival for $1. Obviously Zeke in the beginning was a cheap sneak, though whether that is at all a virtue is debatable. He will advance enough in his vocation to be hated by everyone in the city he lived in but still was in demand for his services. That is when he is noticed by an actual spy organization other than one of his own creation and given a chance to attend a spy school.
We are shown a brief time in Zeke's life when the love of a wonderful woman almost took Zeke from his chosen path, ready to "renounce [his] dirty spy business forever". His conscience, in a strange twist, got the worse of him and reminded him that "once a ratfink, always a ratfink" so bye-bye to the love of his life and his sneaky spying days were back.