"Keigo Demachi is one of the main characters in the Japanese manga series, ""Insects of the Night"". Keigo is a 19-year-old high school student, who lives with his mother and younger sister in a small town. He is a tall and lanky guy with messy, dark hair and deep-set eyes. Keigo is depicted as a quiet and introverted person, who struggles to socialize with his peers due to his reserved nature and lack of confidence.

Keigo has a passion for entomology, the study of insects, and spends most of his free time collecting and studying various species of bugs. Despite his unusual hobby, Keigo is highly skilled in this field, possessing extensive knowledge of insect behavior and physiology. Keigo's love for insects is seen as a reflection of his own personality, as both he and the bugs are perceived as being misunderstood and ostracized from society.

Throughout the series, Keigo's character undergoes a transformation as he becomes embroiled in a series of strange events involving supernatural creatures and a shadowy organization. Keigo's intelligence and resourcefulness are put to the test as he delves deeper into the mystery, uncovering secrets about his own family and lineage.

Keigo's relationship with his family is a significant aspect of his character development. His father was a renowned entomologist who disappeared under mysterious circumstances, leaving behind a legacy that Keigo feels he must live up to. Keigo's mother is supportive of his hobbies but is estranged from him due to their differing personalities. Keigo's younger sister, who is much more outgoing and bubbly than Keigo, serves as a source of emotional support for him, showing him that he is not alone.

Overall, Keigo Demachi is a complex and multifaceted character who embodies the themes of isolation, intellectualism, and self-discovery. Despite facing numerous challenges, Keigo remains dedicated to his passion and becomes a surprising hero in the face of danger."