Naming a module that deals with the meta-object protocol

[Ben Davies]

I wrote a small sum type module that subclasses 
Perl6::Metamodel::SubsetHOW. I was thinking of naming it either 
Type::Sum or Metamodel::SumHOW, but Type::Sum doesn't follow the style 
Rakudo uses for naming MOP classes, and Metamodel::SumHOW may not be a 
good name because it'd leak the module into CORE. What should I call it?