Mamorigatana no Uta: Mamorigatana no Ichimonji

The story takes place in the capital city Shinto Tokyou where humans and monsters live together. The protagonist Uta is bid by her grandmother to find the Makibara Clan, whose household staff were all dismissed recently by the landlord Rinnosuke. The city has also been plagued by series of disappearances involving people being spirited away.

(Source: Anime News Network)