Very much like Yume Nikki had the minigame Nasu .Flow has the minigame Shinsoku Neko. You can play it in Sabitsuki's room by accesssing the gameing console in front of her TV.
The game is simple: earn points by catching fish. These fish will appear as little blue fish that fly across the screen. You must move your little black cat with the directional buttons and catch them using the space bar/z button/enter button. The x button will allow you to dash. There will also be seahorses (the pink and teal things) that when hit will bounce backwards and come back at you this is where the real points are in.
While grabbing a fish nets you 10 points a seahorse's points are determined by how many times you hit it. It starts off at 1 then doubles to 2 and continues doubling till you've hit the highest score possible 999,999 after that it will grant you 999,999 points every time you hit it.
The game is over when all your hearts are gone. You lose hearts every time a fish or seahorse slip past you.