Shinshi Doumei Cross

Shinshi Doumei Cross, which is literally translated to "The Gentlemen Alliance," is a shoujo manga by Arina Tanemura, since 2004. The story is about a 15-year-old high school student named, Otomiya Haine, who attends Imperial Academy (Teikoku Gakuen), an elite private school. She used to be a gang member, but changed her ways when she met a boy named, Shizumasa who encourages her to live the life she wishes to. She now attends Imperial Academy because of him and from that point on, she does everything she can to make herself better and left the life of a gang member, plus she falls in love with him.