Zegapain

Average high school student Kyou Sogoru is an avid swimmer living in beautiful Maihama City. He spends his days hanging out with friends, swimming, and playing video games. However, his normal life turns upside down when a beautiful and mysterious girl named Shizuno Misaki approaches him with a strange request—jump into their school's pool together. This fateful leap transports Kyou into a war-torn world where humans pilot impressive humanoid robots known as Zegas to fight against malicious aliens known as Gards-Orm. To spearhead this endeavor, humans have formed Cerebrum, a rebel organization working to prevent the Gards-Orm from eradicating humankind. As Kyou participates in combat operations, meets his fellow Zega pilots, and witnesses countless deaths, he begins to question the true nature of this world as well as his own life. Kyo, an avid swimmer tries his best to keep the high school swimming club going, which is pretty hard when he’s the only member. Facing the prospect of the club being closed by the student council, he tries to enlist beautiful Misaki to act in a promo video, shot by his good friend Ryoko, in a bid to start a recruitment drive.