Y/N L/N or, as he prefers to call himself, Vanishing Gungaroo, is robot, found by Sara Scorpion's armada, fleeting in space almost deactivated. After being fixed, he joins them as a way to show his gratitude for being saved. Now, serving Sara as explosives specialist, Y/N helps her in quest for Sword of Bernstein, so that she'll become heir to the Imperial Throne. What will happen along the way?