To provide a case allowing easy execution of work such as an insulin self-injection inside a narrow private room such as a toilet without trouble.

In this case 1 installed with a hanging string 13 on a side face of a case body 11, the case body 11 can be opened in a nearly V shape. When suspending the case body 11 in a nearly V-shaped opening state by the hanging string 13, the hanging string 13 installation side of the case body 11 and the opposite side come into a nearly horizontal state. For example, when a shape of the case body 11 suspended by the hanging string 13 and opened in the nearly V shape is triangle, the hanging string 13 is installed to the case body 11 such that plumb lines extending from installation parts of the hanging string 13 pass a gravity center of the triangle or the opening side to the gravity center. Even if the case 1 is suspended by the hanging string 13 and is opened, contents do not fall.