Maken-Ki!

A mercenary unit named Venus is slowly being gathered. Gen learns from Kengo that Takeru tried to break up a fight between two girls before Haruko showed up, but it did not end well. Takeru then receives his Maken from Gen just as Venus arrives on school grounds. Akaya Kodai, commander of Venus, informs Minori that the female members of Venus will be exchange students until summer. He further explains that he is trying to hunt down the culprit who is trying to revive Yamata no Orochi. After the female members formally introduce themselves, Yang Ming, special attack member of Venus, provokes a rivalry with Azuki. To settle the score, Yuka organizes a three-on-three volleyball match in the gym between Haruko, Azuki and Chacha versus vice commander Demitra Midia, defense member Syria Ootsuka and Yang Ming. Aki serves as the referee, while Kodama, Inaho and Kimi serve as the cheerleading section. As the volleyball match progresses, things escalate exponentially, especially since Furan had wagered that Maken-ki would join Venus if they lose. It climaxes to a duel between Haruko and Demitra, destroying the gym. The volleyball match ends in a draw as both sides take a commemorative group photo. (Source: Wikipedia)