In the public studying space, students sometimes hog seats. This behavior prevents others from access their needed seats, and requires man power to patrol and move stuffs from hogged seats to another place. In this paper, we present a capacitive sensor to check seat occupancy statuses in real-time (i.e. un-occupied, people occupying, and seat hogging). The device helps students to find available seats, and helps staffs to monitor seats usage remotely for better controlling over seat hogging problem without the need to patrol. Our experiment results show that the sensor can accurately detect seat occupancy. Moreover, it can clearly distinguish between human occupancy and seat hogging.