Nijuu Yuumu is a Yume Nikki fangame. The game has a total of 15 effects to collect and no ending. Generally, the game's imagery sticks to a naive and simple style, which usually portrays the world seen by a child.

The game features a young girl known as Kizutsuki and her other personality, Kitsutsuki. Some effects can only be used by a certain personality or differ depending on which personality you use.

The money system in this game is different from most fangames, as you can receive money only by finding it. Nijuu Yumuu also doesn't have any vending machines, instead, you can spend your money by buying plant pots in a flower shop.