The House of Oni was a Fallen house that arose during the SIVA crisis, they are a smaller house however still possess a large number of recovered Shanks and Servitors, making the bulk of their militia. Most members of this House consist of former Devils that did not believe SIVA was all-powerful, and still saught the great machine. Come the House-Purge, many of its members joined the House of Dusk, and any other surviving members became freelance- hence dissolving the House.
The House of Oni are of course a split-off faction of the house of Devils, hence many ideals carry over- the only difference is that House Oni do not believe SIVA to be a valuable asset, but rather another tool of the A.I Warmind: Rasputin to destroy them. They do not have Dregs, as all Dregs who're enlisted into the House are relieved of their docking caps- making these Fallen a much more dangerous house- as Ether is not restricted to the Kell and Captains. The large number of Shanks and Se