"Izumi Keito is a major character in the manga series ""The Way to Protect the Female Lead’s Older Brother"". He is a 17-year-old high school student who is the older brother of the female lead, Izumi Mei.

Keito is a tall and handsome young man with short black hair and brown eyes. He is often seen wearing his school uniform or casual clothes. Unlike his sister, who is a popular idol, Keito is a quiet and reserved person who does not enjoy being in the spotlight.

Despite his reserved nature, Keito is fiercely protective of his sister and will do everything in his power to keep her safe from harm. He has a strong sense of responsibility and is always looking out for his family and friends. This makes him a valued member of the cast, as he often acts as a anchor for the more impulsive characters.

Keito is an excellent student and takes his studies seriously. He attends a prestigious high school and is expected to follow in his father's footsteps to become a doctor. However, Keito is unsure about his future and sometimes feels trapped by his family's expectations.

In the series, Keito is shown to have a close relationship with his sister, Mei. They share a deep bond and often confide in each other. Keito is also friendly with the series' male lead, Sakurai Masaya, although the two have very different personalities.

Overall, Izumi Keito is a well-rounded character who adds depth and substance to ""The Way to Protect the Female Lead’s Older Brother"". His loyalty, intelligence, and protectiveness make him a beloved character among fans of the series."