Era of Turmoil

(from ebookjapan):

St. Mary's School for Girls, a beautiful and gentle maiden's castle, was built by the richest man in Japan with the aim of creating a modern-day version of a good old European noblewoman, with a wonderful environment.

However, as ideals go, the environment in which these adolescent girls live is a whirlwind of love and greed! Drawn by the 100,000 monthly part-time job, Masako Natsume accepts a coaching position at the soccer club, a place where especially troubled girls gather!