Okay now this is a Crossmare story, but it's a special Crossmare. It's based on the Empire of the Moon and Empire of the Sun (It's actually all based on the undertale Empire of the Moon and Empire of the Sun, but Crossmare. You'll get it.) Also the title says a bit of it. I hope you enjoy.

Killer x Cross When a Mafia boss falls unexpectedly in love with a total stranger. What is he gonna do?