In 21XX, in an effort to restore the vitality of a nation that was losing its "sense of happiness," the Japanese government established the "Ministry of State Happiness" and created the Showase Amplifier "Clover (CLOVER)." Clover is a mechanism that gives happiness to all people by creating a town called "Habitat" that reproduces Japan in the early 21 century in a virtual space, allowing people connected in a cold sleep state to live there as "avatars," and collecting and redistributing the "sense of happiness" and "happy energy" generated from there through avatars. However, one day, a serious accident of unknown cause occurred, and it was discovered that all avatars with people's awareness on them stopped working on the Habitat, and that the "the 101st person" had illegally connected to the clover, which originally had a capacity of 100 people. Taking the situation seriously, the Ministry of State Happiness urgently summoned a scientist as a "koufuku sousakan (happiness manipulator)" with the authority to manage Clover.