Kyohei Tachibana is a student at a culinary arts school with dreams of someday becoming a patissier (pastry chef). The next step in achieving this goal is to travel to France for some further studying, but there's just one problem: he can't afford it. Instead of giving up on his goal, he gets a part-time job as a cook for a group of four girls; Jo, Meg, Amy, and Sei.
The girls, ranging in ages of eleven to nineteen, turn out to be mercenaries. Despite the fact they're usually being shot at, they all happen to wear the scantiest and tightest choice of clothing possible, which seemingly increases their mobility during combat. Jo is a psychotic sharp-shooting prodigy (as well as the pilot for their cybot mecha, Jango), Meg is the damsel in distress, Amy is a computer whiz, and Sei is their boss, who in turn, works for Bai Lan. Leo, an independent member of the team, operates as Jango's mechanic.