Fastener

The red creature that is often seen together with the Demon Sisters possesses a single zipper on its nose tip and another on the back of its neck. Its eyes lack pupils, and its appearance resembles that of a mantis. It is extremely aggressive and operates the G String. The creature harbors a strong animosity toward Chuck, with a long-standing rivalry dating back to their school days. Furthermore, in the school caste system, it held a higher status than Chuck. When unleashing its full power, it opens the zipper on its neck, transforming into the form of a massive two-headed dragon.