Gakuen Prince(2006)

Gakuen Ouji

Joshi High is an elite school that most girls in Japan only dream of attending. Then one day everything changes–the all-girl school goes coed. There’s just one catch: The girls outnumber the boys. So begins a wild, no-holds-barred competition for the boys of the school. Which smart and independent-minded girl will rise above the fray?

(Source: Kodansha USA)

Note: Includes an extra chapter.