Rising Bliss follows a young guy in his senior year at Kaori Academy who experiences a series of unsettling incidents in modern Japan. The Japanese government is in a dire strait due to the country's falling birthrate, as it cannot fund vital social programs for the elderly, the military, or any other essential social function. Prime Minister Tachi responds by creating a potent aphrodisiac and introducing it into the water supply. As people succumb to their lust, society as a whole soon loses its moral grounding and becomes more indulgent when it comes to sexual behavior. The population is preoccupied with mindless mating as the Minister consolidates his power to rule a sex empire for the rest of his life. Things don't go as planned, though, as the infected quickly overwhelm the city of Tokyo. The contaminated water supply was ideal for developing a new disease - the BLISS VIRUS! The protagonist and his classmates are in danger from a horde of lust zombies, and he must do everything possible to get them out of the city alive.