WARNING: The following contains spoilers for Rust-Eater Bisco Season 1, Episode 9, "I Love You," now streaming on Crunchyroll.
Episode 9 of Rust-Eater Bisco continued with the same level of emotional resonance as recent episodes have had, giving fans bits of poignancy before delivering a lasting, devastating blow. The battle against Kurokawa has spanned a few episodes, with each one further hinting at the possibility of death among Bisco, Milo, Jabi and Pawoo. The start of Episode 9 gave fans a bit of a fake-out, but the shock of death inevitably arrived before the episode's end -- albeit for someone audiences may not have expected.
By the end of Episode 8, it seemed likely that Milo would succumb to the grave injuries he sustained while trying to escape with an injured Bisco. The episode ended with Bisco tearfully watching his friend in the midst of chaos, and Episode 9 gracefully continued the mournful beat. Opening with Milo running toward a smiling Bisco, Jabi and Pawoo in a field, it's hard not to think this is a vision of peace shown in his final moments. Milo quickly finds that he's unable to reach his new family, as they get further and further away despite how hard he runs, until he's finally jolted awake.
Both he and Bisco are in terrible shape, with the Rusting having spread on both their bodies. As he takes care of a temporarily-blinded Milo, it's obvious that the Rusting has taken a far greater toll on Bisco's body. At this point, there's no word on Jabi's condition after being bombarded by Kurokawa's soldiers, and Pawoo has yet to return.
Bisco and Milo are both struggling to fend off the throes of death, but the tension is dissolved by the tender interactions between the two as Bisco comforts Milo. The two have quickly developed a relationship that runs deep, with Bisco even likening it to how Jabi must have felt while raising him. While Bisco promises Milo that he'll be by his side when he re-awakens later, the dire circumstances and Bisco's past actions make clear that this is likely to be his last moments with Milo.
The episode then shifts its focus to an injured Kurokawa and Jabi, who has been captured again. However, rather than kill him, Kurokawa tells Jabi about his plan in the hopes that he will help by gathering any remaining Mushroom Keepers so he can use their blood to synthesize medicine against the Rusting. He plans to continue monopolizing the treatment but laments that the availability of one has reduced the number of infections. As such, he reveals his intent to further the spread of the Rusting through artificial means by using the Tetsujin -- the device that caused the Rusting in the first place.
However, Kurokawa plans to weaponize the Tetsujin with the molten rust he's amassed in a limited capacity, fearing its full power. His fear hints at the still-unsolved mystery as to why the Tetsujin were created and used in the first place, and whether this was also driven by the desire to capitalize on something necessary for survival in the wake of disaster.
As has become characteristic of the anime, Bisco appears at the last second to save Jabi, having disguised himself as one of Kurokawa's special forces. Similar to his moments with Milo, Bisco and Jabi share one final, touching embrace as he thanks Jabi for raising him and teaching him all he knows. Jabi eventually encounters Pawoo outside as they take on more of Kurokawa's creations, while Bisco and Kurokawa face off to the death. With his Rusting so severe, Bisco's body literally begins to fall apart as he fights, but that doesn't stop him from telling the governor that he intends to kill him even if it costs him his own life.
In spite of his tenacity, the state of Bisco's body makes it seem like even this final act might be impossible. Thankfully, Milo appears to assist, stopping Kurokawa from killing Bisco so that he can deliver the final blow. Bisco's final lunge sends both of them into the molten rust, leaving Milo to watch helplessly as Bisco is forced to sink to his death.
With Kurokawa finally dead and his own death inevitable, Bisco asks Milo to shoot him with an arrow so that the rust isn't what takes his life. He tells Milo that, no matter what, he and all that he taught him will be there to protect him when Milo needs it most. When Milo looses an arrow and reveals his love for Bisco, the anguish over Bisco's death is rivaled by the looming question of whether or not Milo, Jabi and Pawoo can fulfill Bisco's mission and keep Kurokawa's plan from succeeding.
