The game's overall theme is "saving the world with a kiss". The main character, a boy called Ryoma, has the ability to "kiss", and, in effect, "absorb" energy from enemies, and use that energy to create "miracles". The game's setting has been described as a combination of an otherworldly fantasy land that was abruptly fused with one more like a "modern-day Tokyo", with the game depicting the repercussions of such an event. Source: Wikipedia, "Exstetra," available under the CC-BY-SA License.