Morihito Otogi's family is descended from a long line of ogre familiars, and he has the inhuman strength to prove it. One day, his father comes to him with the life-changing news that he is to become the familiar of his childhood friend, the teenage witch Nico. He is to live under the same roof with her and protect her from anything and anyone that may attempt to harm her. Meanwhile, Nico is excited to get to live with the love of her life, even if her crush is one-sided—Morihito is so serious about his duties to protect her that any romance is going to be an uphill battle. But he has every reason to be serious, as Nico has a prophecy of doom hanging over her head! Morihito Otogi's surprisingly quiet life of being a human with the monstrous strength of an ogre is turned upside down when his father comes to him with life-changing news. He is to become the familiar of his childhood friend Nico, a teenage witch—and the two are going to live together, alone, under the same roof! Nico is head over heels in love with Morihito and wants to have a perfect, normal, high school rom-com life with him! But with all of the magical hijinks and trouble she leaves in her wake, Nico's got a long road ahead of her if she wants to get more familiar with her familiar.