"Negotiation" (折衝 Sesshō?) is the 91st chapter of the Toaru Kagaku no Railgun manga series, released on December 26th 2016.
- Mikoto continues her battle with Ryouko with the support of Misaki.
- After supporting Mikoto for their own ends, Scavenger successfully completes their mission on a technicality and abandons Misaka Mikoto.
By order of appearance:
- Electromaster (Railgun-variant) - Misaka Mikoto, Level 5
- Mental Out - Shokuhou Misaki, Level 5
- Predator - Leader, Level 3
- 'Soul Possession' - Doppelganger
- Stick Slip - Seike, Level Unknown
- Perfect Paper - Naru, Level 3
- Mix Master - Yakumaru, Level Unknown
- Academy City Air Traffic Control Search Radar (referenced only)
- Warehouse No. 8086
- Mikoto notes the similarity between the Doppelganger and Sherry Cromwell's Ellis golem she fought after the end of summer vacation back in Index Light Novel Volume 6, in which adpated to Index Episode 21.