Asylumstuck, sadstuck. A boy wakes up in an asylum with almost no memory of his past. A girls has visions of horrific creatures that dwell in the darkness, but no one else can see. A boy who doesn't seem to belong in a mental hospital avoids telling anyone why he's there. A girl is raised by a dog on a deserted island and is found years later, feral and dangerous.

Planeptune is on its last limbs. Shares are at an all time low, Neptune has run herself ragged trying to support what's left of her country, and Nepgear has been comatose for weeks. Fearing the demise of their nation imminent, Histoire summons the other CPUs to request that they save Planeptune, using the only means left: One of the CPUs... must marry Neptune. [Part 3 is here!]