Synopsis: Taki Juhas is the oldest of ten children and his parents apparently owe a debt to the local Catholic church. In lieu of paying off the debt, the priest Shikimi Farkash comes and takes Taki as his indentured servant. As Taki spends his time cleaning the giant cathedral and serving his sensei tea, he wonders why on Earth they need to keep such a secluded church so clean. That night, Shikimi introduces Taki to the other part of his job - zombie killing.
Though there seems to be a bit of a misunderstanding about how the Catholic church works in this comic (owing debts to the church that are repaid with indentured servitude, and as a priest's servant, Taki is given a priest's outfit to wear) it doesn't really seem to affect the overall story.
Taki and Shikimi are both very attractive, and just seeing the cover one might think that there is going to be some shonen-ai going on, but that is definitely not the case. Their relationship is mostly humorous, with Shikimi being unreadably cheerful, and Taki being a teenage grump, always about to pull one over on his new master (like giving him mop water in his tea).
Supernatural elements of the story are introduced to us through Taki's introduction to them, and then Shikimi explains them. Shikimi hands Taki a sword and takes him to the graveyard to "see how he reacts" on his first night. Once a zombie pops up, and Taki kills it, Shikimi explains "Oh, that was the dead fisherman's wife we buried three days ago." It lets the story unfold and get explained to the reader very quickly, but it doesn't leave much to be answered in the next book. But now I really enjoy the characters, so I'm still going to read the next book (perhaps that was the point all along).
As Taki learns more about killing zombies that rise from the church's graveyard, Shikimi begins to reveal the reasons behind his silver hair (which seems to demonic to the townspeople) and why Taki is just so dang good at killing zombies. Though usually, he's not good enough for Shikimi, who critiques him constantly - "You used way too much energy getting the head off of that one."
Overall, it's like a supernatural slice-of-life friendship between unlikely people manga, and I think you'd like it.