Disclosed is a magnetic device including a spin sinker. The magnetic device includes a storage medium, a spin sinker, and a read node. The storage medium receives an in-plane current from outside and generates a self-generated spin current that perpendicularly flows to a charge current, thereby controlling a data structure with the self-generated spin current. The spin sinker receives and attenuates the spin current. The read node measures a magnetoresistance of a data structure through the storage medium. The storage medium is made of a magnetic metal and the spin sinker is made of a magnetic insulating material.