Tsukumogami: spirits -- or "marebito" -- which have possessed objects of considerable age and gained a physical form. Although he is part of the Saenome clan which is charged with peacefully sending them back to their own world, Kunato Hyouma hates their guts because one took away what was very precious to him. In order to cure him of this loathing, Hyouma's grandfather sends him to live with Nagatsuki Botan, a girl who is the master of six "friendly" tsukumogami and lives with them as a family.

From Easy Going Scans:

Crimes commited using manned combat-androids dubbed "Katana" run rampant.
In an effort to maintain order, the government has organized the AKCD - "Anti Katana Crime Division."
Togusa of the 8th squad of the AKCD, while holding existential doubts as a Human-Katana hybrid, continually casts himself into battle...