When boys suddenly get into places where they've never been allowed before, some girls tend to get upset. So when the decision is made to merge the elite Yuihime Girls' Private Academy and the coeducational Kagamidai Private Academy, everyone wants to take extra care in avoiding trouble while bringing the two Privates together. Therefore, rather than just sticking the Kagamidai boys into the Yuihime girls all at once, a plan is concocted in which a group of test males will be inserted into the Girls' Private Academy first. 
Thus it is that poor young Shingo finds himself being thrown as a sacrificial lamb to the lionesses of Yuihime, who aren't exactly waiting for him with open arms. Will Shingo manage to survive the estrogen soaked death pit that is Yuihime? Can the girls learn to be more receptive to the boys? And just how long until something involving panties will cause emotions to flare, sparks to fly and the battle of the sexes to explode? 
(Source: Sentai Filmworks)

DVD/BD specials of Mashiroiro Symphony: The Color of Lovers.

An alternate ending to the anime with Airi being the chosen girl. This is not animated in a normal anime fashion, it is more of a gal game animation.

This is the official comic based on the game of the same name. An all-girl's school is preparing to consolidate with another nearby school, which will make them co-ed. Uryuu Shingo is chosen to be a male 'test student' at the girl's school before they officially merge in the following year. On Shingo's first day, he learns that many of the girls are not happy about the coming merger. Specifically, Seno Airi is staunchly opposed and refuses to welcome him to the school. Some of the other girls are friendly, but Airi has a lot of power over public opinion. The truth is, though, that Shingo has met Airi before. When she and Shingo's little sister got lost, he helped them find their way. Airi seemed to like him then, back when she didn't know he was going to be her new male classmate. Maybe he'll be able to win over Airi, as well as all his other interesting female classmates! 
(Source: MangaHelpers)

Tags