Vandread : Enemy Engaged (Vol. 1)

Men and women live on separate planets (Talac and Majel) in a state of mutual hostility and ignorance. Mechanic, third-class citizen and underdog hero Hibiki stows away aboard the new Talac flagship which gets caught by attacking Majel pirates. He's thrown into contact with Dirda during a battle, she cries, 'These guys are really bad aliens!'. The scantily clad women are then forced to enlist the aid of Hibiki and two other male prisoners when they are attacked by unknown aliens.