Speaking of characters, players can choose one of two main characters to play as in Twin Age -- Aldo and Reiha. Aldo is a male Summon Beast and Reiha is a human girl, and the two live together as brother and sister among the tribe of the Kascuza, a race that are essentially half-human and half-beastmen in nature. As the game starts, the duo lives in peace, but in typical RPG fashion, they will soon get caught in a major conflict, ultimately finding themselves and a random collection of allies forced to save the world from calamity. The story differs somewhat based on which main character is selected, but either way, it is still pretty much just typical RPG stuff -- nothing great, but passable.
As mentioned above, the true highlight of Summon Night: Twin Age is the way it embraces the platform for which it was created. This is a Nintendo DS RPG through and through. In addition to using the stylus for movement and for launching into normal attacks, the stylus is used to launch special attacks. Once selecting a technique or magic attack, the player uses the touch screen to select targets by drawing lines, tapping opponents in rapid succession, and so on. Plus, the dual-screens allow players to keep track of maps, party status, special attack instructions, and the like in the heat of battle. Even shopping is easier, as party information is listed on the top screen and merchandise on the bottom. In all the technical ways, the developers have taken great care to create an immensely user-friendly product.