I've mentioned this in IRC as well, but I'm posting here for formality as well.
The issue seems to revolve around perl-dprof. I've found a few things:
1) perl-dprof is deprecated according to upstream
2) The arch package of perl dprof has nothing after it where other groups are equal to some number as seen here http://www.archlinux.org/packages/core/x86_64/perl/
3) I've noticed that for me the error only occurs when trying to interact with the aur, but not by calling out to pacman proper.
4) The error occurs when installing anything from the AUR not just things that depend on perl.
This leads me to think that the error exists in dealing with the aur, but it is for some reason looking at the perl groups? I'm not sure why.
Downgrading the perl package from 5.14.2-5 to 5.14.2-4 fixed the issue. However, I still think that the behavior is broken. Why look at a package in core for installing something in the aur that doesn't depend on the core package?