Mikoto, who works at the happiness store, is actually a princess from another world, Wonderland.
The "happy garden" in the wonderland of the world where Mikoto lived is about to die.
When the Garden of Happiness fades, the power of Wonderland is weakened and in the worst case it is threatened with extinction ...
In order to save Wonderland from this situation, you have to collect Happiness Points ...
Once the happiness points are collected, the garden of happiness will return to its original state.
And there is only one way to accumulate "happiness points" ...
so that people in this world feel happy.