The episode begins back when Souma made curry at Kei’s, and gives us more of the conversation they had, specifically the trickiness of their struggle against Urachi. Their adversary has devised a number of contingencies such that any attempt to undo his plans will be thwarted.
Souma laments that she’s thus far been unable to find a way around those contingencies in order to save the abilities of Sakurada, so she asks Kei to use her precognition to find the best possible future for himself; the one she couldn’t find. For Kei, that’s a future in which Souma doesn’t disappear.
Back in the recently reset present, Souma is about to meet with Urachi at the cafe, but changes course, instigating a pursuit by Urachi and Sakuin. Kei heads to the waterfront with the photo of Souma (whose ability he’ll borrow) Haruki (whose future he’ll read), Sakagami (who’ll be the means of borrowing Souma’s power) and Tomoki (to keep track of time and communicate with the other Souma).
It’s quite an intricate little plan, with a lot at stake and in which timing is everything. The moment Kei gains Photo Souma’s precognitive ability and Haruki speaks to him, the look on his face says it all…but in his infinite coyness, he reveals next to nothing in the way of actual details regarding that future.
Meanwhile, Souma is quickly caught and cornered on the top of a fire escape by Urachi and Sakuin, and believing her work to be done, is prepared to jump over the edge to prevent herself from being taken hostage, and thus becoming a potential liability to Kei.
But since Kei can see Souma’s future as well as Urachi’s, he knows what she’s about to do, and stops her before she can, using Tomoki as a go-between. Instead, he tells her he has to meet her again, and has her wait five more minutes, during which time she tells Urcachi what she really is (‘not’ Souma) and the mistakes he made that allowed Kei to reset.
What she doesn’t tell Urachi is what Kei did with his planner in the timeline with no abilities, in which Urachi has a gap in his memories. That’s because the five minutes are up, Souma jumps off the ledge, and rather than fall to her death, she’s caught by Murase (Hi Murase!), who Kei just so happened to have searching for her.
As Kei learns more and more of the futures of Haruki, Souma, and himself, he gives Souma very precise instructions on how to leave Sakurada until returning noon tomorrow. All the while, Kei is conversing with Haruki about favorite colors, and how Haruki has come to like a lot of things she once had no preference for.
It’s that Haruki Kei wants to preserve, as well as all of the abilities in Sakurada. But he won’t do that by sacrificing Souma; he wants her to be able to live a life where she’ll be able to wake up and go to sleep happy day after day.
Is he being selfish, insisting on so many conditions for victory? Perhaps, but as the only person in Sakurada who will always remember everything, no matter what, it’s kinda his show.