This is a list of fictional characters appearing in the Japanese manga series Monster Musume, which is serialized in the magazine Monthly Comic Ryū, published by Tokuma Shoten.
Main characters
Kimihito Kurusu
is a normal Japanese student living in Asaka, Saitama in his parents' home while they are temporarily working abroad, with a part-time job and all the dreams and feelings that young people have. However, through no fault of his own, he is literally thrown into the world of the Interspecies Cultural Exchange Accord and becomes a "host family" to a group of liminals, or "monster girls", and can only watch helplessly as Ms. Smith has his house remodeled over and over again to accommodate each newcomer. Kimihito seems to excel at certain household chores and activities: his cooking is so good that the liminal girls living with him put on weight, and he proves to be quite skillful with needle, thread and sewing machine. Another talent (instinctively but unwillingly acquired and later eagerly demanded) is his skill at and technique of milking Minotaurs and Pans by hand (a skill that later makes him a target for the Satyr girls who also work at the farm).
Almost none of the other characters call Kimihito by his actual name, except for Ms. Smith in the first chapter and Manako as of Chapter 42. The girls seem to fall in love with him simply because he is nice, friendly and modest, and because he treats the "monster" girls as ordinary, real people — not as exotic or dangerous creatures; he is so unconsciously adept at this (perhaps because it is part of his personality) that he seems to become friends with other liminals with astonishing ease. He is also not afraid to unhesitatingly put himself in physical danger to protect or save his liminal house-guests, whom he thinks of as family, as demonstrated on several occasions such as bodily shielding Centorea from a sword attack, trying to save an injured Mero or nearly being absorbed by a giant-sized slime liminal while trying to save Suu.
Considering everything happening to him and going on around him, he has a very patient but long-suffering nature, and he accepts being put upon by Ms. Smith (and later the girls of the MON squad) with good grace, but he does care very much about his house-guests' well-being. He rarely shows any anger towards anyone, especially the girls, but when he does he demonstrates a surprisingly strong assertiveness, two of the most notorious examples occurring first because the Couple (see "Supporting Characters" below) insulted Miia and second because Lala was playing with her food instead of eating it - which prompted all the others to ensure that they clean their plates from then on.
In Yoshino Origuchi's light novel Monster Girls on the Job (2020, Seven Seas Entertainment, ), he accompanies all of his homestay girls and the MON members on their various jobs as part of the new Interspecies Cultural Exchange Work Program.
Miia
is a lamiai (part woman, part snake), the first liminal to live with Kimihito. She is about long, but always moves with her front upright, so she appears to have normal human height. She has red hair, golden eyes with vertical slit pupils and pale human skin, and her snake part has copper scales with a pinkish-cream underbelly (the tip of her tail is particularly sensitive). Her standard accessory is a pair of D-shaped hair clips, which are a standard fashion statement among her people. Unlike snakes that have no visual outer ear, Miia has rather large triangular, scaly ears. She is a poikilotherm, which makes her drowsy in mornings or cold weather and can be considerably dangerous for her if she enters cold water.
She has a pleasant personality and harbors a very strong crush (both figuratively and literally, considering that her species is a constrictor) on Kimihito — actually on the brink of the obsessive: all lamiai are female — they need a human male for procreation and are very passionate about their partners. In Chapter 27, it is revealed that Miia's original reason for studying abroad was to find a "tribal husband" for her home village: the lamiai custom was that a human male would be "coerced" (taken against his will) and brought back to be shared among all the lamiais, but when the Interspecies Exchange Accord was enacted and laws were passed protecting humans from liminals, that method had to be abandoned. However, after getting to know Kimihito, Miia fell madly in love with him. It's also revealed (by Miia's mother) that at some point Miia's father escaped from the lamiai tribe.