Look at the poor Sushi Cat, he wants to get the cute cat stuff toy that he saw in the window but he can get into the building because he is under weight. He needs to gain weight and he saw sushi in the corner which he loves to eat that is also why he is called Sushi Cat.
In this game of Sushi Cat you need to help the poor cat to gain weight by eating all the sushi in weight as much as possible to gain weight and get fat. The door doesn’t react in his weight that is why it doesn’t open. That is the reason he needs to get fat to be able to enter to the automatic door and to be able to get the cat stuff toy. Guide and drop the cat at the sushi that he need to eat.