Maria Naruse

Maria Naruse is a succubus and Mio Naruse's Guardian after the death of her adoptive parents. She is the daughter of Sheila and little sister of Lucia, it is later revealed that Maria is also the daughter of Wilbert, thus making her the niece of Sapphire, the younger half-sister of Mio, and the cousin of Basara Toujou. Maria is a petite beautiful girl with long silver hair and purple eyes in her human form most of the time. She is seen dressed in a black dress that has white frills most of the time and what seemed to be like a functional keyhole on her collar, where her magical key is meant to be inserted in, black leggings, and boots that have a purple hearts on them. In her succubus form, she has slit purple eyes and small black horns on her head, dressed in a black leather revealing outfit, white leggings with light pink horizontal stripes, and black boots, as well as small black wings located near her waist. When using her Magic Key, Maria takes on the form of a full-grown older woman with a curvaceous figure, large breasts surpassing Mio, and was taller and slender compared to Yuki, as well as thick black gauntlets. In volume 11, when she uses her Reverse Magic Key, instead of taking on the form of a curvaceous older woman, Maria maintains her normal stature. While in this form, Maria has thicker and longer black horns, a longer tail, and a more elaborate cross-shaped keyhole. Maria is rather childish and likes teasing people no matter how serious the situation. She prides herself on trying to make light of most situations to counter the seriousness of Basara and the rest of the harem. She's often referred to as being the "problematic" member of the family due to how brutally honest she is about her feelings and desires. Being a succubus, Maria naturally feeds off of the lewd situations. In the first half of the series, she's primarily scheming and watching Basara engage in lewd acts with the rest of the harem in order to deepen their bonds. However, in the second half of the series, she becomes an active participant in the lewd situations, and even discovers that she's a bit of a prude and a masochist when it comes to others watching her engage in lewd acts with Basara. Outside of being a prankster and tease, Maria has a vulnerable side. As a child, she was repeatedly told that her mother's appearance was her fault. Maria then internalized that and spends the majority of the series blaming herself for her mother's condition. She also has moments, quite a few moments, where she's brought to tears and questions her worth and role in Toujou Residence. According to Sheila, although Maria is an experienced succubus, she's inexperienced when it comes to being a girl. She's in love with Basara, as with the other members of the harem. However, unlike the other girls, Maria often pushes her feelings down, and rationalizes it by saying "she's supporting Basara deepening his bonds with the other girls". She has some moments though where she puts her feelings first and rewards herself with quality time with Basara. Maria also values the other girls in the harem and is good friends with them. She's good at keeping some of the more embarrassing secrets of some of the girls and does everything she can to help when they might be in a pinch.