Obsessed Kunoichi Satsuki

You're the 5th son of a noble house, knowing that you weren't going to be able to inherit any political power from your family you set off as an adventurer to avoid a power struggle. As a parting gift your father gifted you Saksuki, one of his assassins, as a body guard in your journeys. Thrilled at first to have a power bodyguard, you soon realize that she's harboring an unhealthy obsession.