Biofilms are slimy aggregates formed by microorganisms, which can harm the environment with significant energy losses. "Quorum Hacker" is a molecular robot that contributes to the decarbonized society by preventing the formation of biofilms by blocking the communication system among bacteria: quorum sensing. Its basic framework is a giant vesicle consisting of three parts: a sensor which detects the quormone (molecule used in quorum sensing), a processor which verifies the concentration of quormone and activates the producer of the aptamers, and an actuator which creates the pore into the giant vesicle for releasing the aptamers. When detected quormone, "Quorum Hacker" releases the DNA aptamers to inhibit quorum sensing among biofilm-forming bacteria.