Button

Button is one of 92 magical spider summoned by Lolth in Session 6: A wide variety of deeply concerning things. He was captured (and subsequently named) by Natsu in Session 7: Full Moon in Polaris(report:99579331-895b-4307-8cc2-edc97b71323b).  Over time, it was revealed that Button, like all spiders, was beholden to @[Lolth and serving as a spy.  He also multiplied multiple times, and was later convinced to leave Barry the Airship to explore other ships.  This spawned what would later become a continent-wide spider epidemic.