Toaru Kagaku no Railgun T

御坂美琴が飛行船を破壊し、双葉理央を救うというドッペルゲンガーの最後の願いを叶える

Learning that Doppelgänger's objective was to end her life and destroy the data that could rebuild her, Mikoto respects her wishes and destroys the airship. Before Mikoto can finish off Doppelgänger, one of the scientists' attempts to take Ryouko hostage to stop her, accidentally shooting her in the process. In her final moments, Doppelgänger asks Mikoto to use what's left of her cyborg body to save Ryouko. Later, the Scavengers increase their rank in exchange for not getting paid for their mission while Mitsuko is formally introduced to Misaka 10032. Meanwhile, Doppelgänger appears in Ryouko's dream, suggesting that she now coexists inside her body. (Source: Wikipedia)