Funeral Procession of K

From Maki Kusumoto, author and illustrator of Die Todliche Dolis and Hikarabita Taiji It's Japanese name is "K no Souretsu"

Summary
Mikaya, moving into an apartment investigates into the mysterious death of a man named "K" who used to live in the same room as the one he's moving into. The day he moves in, all the residents were doing a funeral procession in honor of K, but there was no body in the casket. Dispite not having a corpse, everyone of the apartment are absolutely certain that K is dead. As the story unfolds, Mikaya dwells deeper into the mystery, and finds himself plagued by disturbing dreams of K. Mikaya's disturbing journey continues in the manga's second volume, revealing his true connection with K and K's story.