Kanan Takakiyo is the female protagonist of the romantic comedy series. She is a demon from the demon world who has come to the human realm with the specific goal of devouring human souls, which she finds particularly delicious, especially those of the young and vibrant. To carry out this mission, she infiltrates Tama Municipal Votive Academy, posing as a seemingly perfect human high school student. At school, she holds the prestigious position of chair of the discipline committee, where she is known for being popular, athletic, and respected by the student body. Despite her youthful appearance as a sixteen-year-old girl, Kanan is over a thousand years old, being the daughter of a notable demon named Beelkzabub.

In terms of personality, Kanan displays a fascinating duality. On the surface, she is a smug, charismatic, and dominant demoness who carries herself with an air of elegance and control, presenting herself as the "Gourmet Devil". However, this confident exterior masks a deep and comical inexperience when it comes to romance and personal feelings. Having lived for centuries without ever falling in love, she is incredibly naive and shy in matters of the heart. She is described as expressive, clumsy, and something of an airhead, prone to short-circuiting and blushing furiously when confronted with genuine affection or bold romantic gestures. This contrast between her fearsome demonic identity and her easily flustered, bashful true nature is a central aspect of her character. She also has a notably jealous and possessive streak, quickly becoming territorial over the boy she likes if other women show interest in him.

Kanan's primary motivation shifts dramatically over the course of the story. She originally arrives in the human world with a clear, predatory plan: to treat humans as livestock and harvest their souls for her sustenance. Her plan begins to unravel when she selects a junior student named Yoji Kyogi as her first target. She summons him with the intention of devouring his soul, but a critical misunderstanding leads Yoji to believe she is confessing her love to him. Rather than running in fear, Yoji asserts that they are now boyfriend and girlfriend. Completely unprepared for this development and charmed by his assertive and earnest nature, Kanan finds herself agreeing to a romantic contract with the very person she intended to consume. Her motivation thus evolves from hunting for a meal to navigating the overwhelming, confusing, and sweet emotions of her first love, as she is drawn deeper into a genuine relationship.

In the story, Kanan serves as the central figure around whom the supernatural and comedic conflicts revolve. Her role is that of a powerful demon whose dark plans are constantly derailed by the innocent yet relentless affection of her human boyfriend, Yoji. She is joined in her daily life by Ami, her loyal maid from the demon world, and Jeanne, a clumsy apostle of God from the heavenly realm who adds another layer of supernatural chaos to her life. Her key relationship is, of course, with Yoji Kyogi. He is the primary catalyst for her emotional development, as his straightforward and positive personality consistently catches her off guard and melts her demonic resolve. Her development involves a slow but steady journey from a predatory demon solely focused on her mission to a young woman grappling with jealousy, shyness, and the genuine desire for a romantic partnership, often finding herself led around by Yoji's actions.

Regarding her notable abilities, Kanan possesses the supernatural powers inherent to a demon, which include the ability to devour human souls. For visual effect, she can also project an intimidating demonic aura. She has a unique physical trait where her characteristic twintails are not just a hairstyle but are secretly her demonic horns. Despite her age and power, her most defining "weakness" is her complete lack of emotional defense against sincere romantic advances, a trait that makes her, as the title suggests, devilishly easy to fluster.