Shiina Mahiru is the female lead of The Angel Next Door Spoils Me Rotten. She is the next-door neighbor of Amane Fujimiya and attends the same high school.

Every part of Mahiru's appearance is synonymous with beautiful, and she is often inseparably described as such. Her blond hair is always straight, well-groomed, flaxen, silky smooth, and lustrous. Her large eyes are caramel colored, with long lashes, both top, and bottom. In addition, Mahiru possesses pale, milky-white, soft, perfect skin and a shapely nose.