neet de otaku na kunoichi to naze ka dousei hajimemashita
Somehow,_I_Started_Living_With_a_NEET_Otaku_Kunoichi ニートくノ一 ニートでオタクなくノ一となぜか同棲はじめました neet_kunoichi
Webmanga by koyuki.
A salaryman lives with a kunoichi that protects him from demons summoned by an ancient family curse. However, when not slaying monsters she spends her time as a layabout game otaku.