A case device comprising: a housing including an upper face and at least one recess formed through the upper face designed to accommodate at least one earphone device; a cover configured to cover the at least one recess in a closed state and to allow access to the at least one recess in an opened state, the cover including a first peripheral portion that is opposite to a first portion of the housing at one side with respect to the at least one recess and a second peripheral portion that is separably connected to a second portion of the housing at the other side opposite the one side with respect to the at least one recess; a hinge portion configured to connect the first peripheral portion of the cover to the first portion of the housing; a first magnet disposed in the cover through the hinge portion, and a second magnet disposed along the upper face of the housing to face the first magnet, wherein the first magnet and the second magnet are disposed such that the attractive force gradually increases in a direction in which the cover is opened when the cover is opened; a third magnet disposed in the second peripheral portion of the cover; a fourth magnet disposed in the second peripheral portion near the third magnet and having a polarity opposite the polarity of the third magnet; a fifth magnet movably disposed in the housing, wherein the fifth magnet is configured to: hold the cover in a state of being closed to the housing when disposed so as to generate an attractive force at a position where the fifth magnet reacts to the magnetic force of the third magnet, and open the cover from the housing when shifted to a position where the fifth magnet reacts to the magnetic force of the fourth magnet and generates a repulsive force. a housing including an upper face and at least one recess formed through the upper face designed to accommodate at least one earphone device; a cover configured to cover the at least one recess in a closed state and to allow access to the at least one recess in an opened state, the cover including a first peripheral portion that is opposite to a first portion of the housing at one side with respect to the at least one recess and a second peripheral portion that is separably connected to a second portion of the housing at the other side opposite the one side with respect to the at least one recess; a hinge portion configured to connect the first peripheral portion of the cover to the first portion of the housing; a first magnet disposed in the cover through the hinge portion, and a second magnet disposed along the upper face of the housing to face the first magnet, wherein the first magnet and the second magnet are disposed such that the attractive force gradually increases in a direction in which the cover is opened when the cover is opened; a third magnet disposed in the second peripheral portion of the cover; a fourth magnet disposed in the second peripheral portion near the third magnet and having a polarity opposite the polarity of the third magnet; a fifth magnet movably disposed in the housing, wherein the fifth magnet is configured to: hold the cover in a state of being closed to the housing when disposed so as to generate an attractive force at a position where the fifth magnet reacts to the magnetic force of the third magnet, and open the cover from the housing when shifted to a position where the fifth magnet reacts to the magnetic force of the fourth magnet and generates a repulsive force. hold the cover in a state of being closed to the housing when disposed so as to generate an attractive force at a position where the fifth magnet reacts to the magnetic force of the third magnet, and open the cover from the housing when shifted to a position where the fifth magnet reacts to the magnetic force of the fourth magnet and generates a repulsive force.