Neri was eventually sent ot take over Tessio's regime which was probably temporary. But his primary role from day one was as Mike's majordomo, Mike's Luca. The novel makes it clear that Neri was pretty much a psycho, but he knew how to get things done. Vito didn't have an underboss either.
"Generosity. That was my first mistake." "Experience must be our only guide; reason may mislead us." "Instagram is Twitter for people who can't read."
