ippon Ichi's Hyperdimension Neptunia has seen a number of entries to its series over the course of the last five years or so. Most, if not all, have seen release in North America, two of which made it to the Playstation Vita; June's Hyper Dimension Neptunia: Producing Perfection was a shallow, mostly pointless mass of fanservice code that should pretty much be ignored. Hyperdimension Neptunia: Re:Birth 1st, however, is worth a much closer look.
You would be forgiven if you didn't realize going into it that Re:Birth 1st is a actually remake of the first entry in the series; albeit heavily remixed one, but that's exactly what it is. It tells the story of a fictional (and literal) console war, with nations modelled after all of the popular console brands you can find on store shelves even today. In each nation, a powerful goddess called a CPU fights for shares which represent their respective power amongst each other. Their battles were fierce and one CPU, Neptune, fell, crashed amongst the people of Gamindustri, and lost her memory. That's where the very typical story of Hyperdimension Neptunia picks up.