Three girls - Natsumi, Ayane and Haruna own a courier shop called Rapid Angel. When the girls take on the task of delivering some important blueprints it turns out that an evil organization is after these papers too.
Rapid Angel is a mix of 2D platformer and beat-'em-up, so the players will explore the levels fighting enemies, collecting power-ups and avoiding traps. While basic moves are the same for all characters (running, double-jumping, using bombs etc.), each girl has her unique fighting style with Natsumi and Ayane relying on physical attacks and Haruna using mostly distance-type magic attacks. Particular fragments of levels and story sequences are different depending on the character chosen by the player. Two more characters are unlocked after beating the game.
In 2-player mode the second player controls an angel-thing that follows the first player's character aiding him along the way.