Touhou Shinigami - Meteor Methuselah Gaiden

Zol, a bounty hunter who goes by the name of "Grim Reaper", spends his days chasing criminals under the orders of Fuse, his master and the city's respected major. One day, Zol takes up responsibility for burying a man who died in a hit-and-run on the streets. But much to his surprise, the supposedly dead man pops out of the coffin!! Is this the world's most wanted man, Methuselah?!
This is the adventure-packed tale of the fateful encounter between Zol, the "Grim Reaper" and grandfather to Meteor Methuselah's super heroine Machika, and the Methuselah named Rain!!

A miniseries prequel about the encounter between Rain and Zol.