Mikoto and Kuroko get in trouble for using their powers in the dorm. Their punishment: pool cleaning duty! Later, Kuroko finds herself feeling frisky after accidentally ingesting a powerful aphrodisiac!

Someone is planting bombs all over Academy City, and it’s up to Judgment to stop the person responsible. Mikoto, wanting a piece of the action, uses Uiharu’s badge to investigate on her own.

Misaka and the girls decide to play matchmaker with their dorm’s Head Resident and Daigo, Uiharu and Saten's teacher. Things look to be working out - until Daigo brings up the subject of marriage.

The midsummer festival arrives, and students are preparing to show off their school for friends and family. Misaka’s scheduled to perform a violin solo for the festivities - if her nerves don’t get the best of her!

After dreaming of her past, Misaka sets out for a day of shopping, but when Kuroko suggests a shortcut, they find an envelope with a cash card in it--one of many placed throughout town. Elsewhere, Saten thinks she sees someone who looks like Misaka.

Misaka manages to sabotage most of the experimental facilities remotely before she is cut off, leaving her to deal with the rest in person. Shirai resolves to help Misaka by doing her part to be more vigilant at work, but risks shutting the others out.

While Shirai frets about Misaka staying out again all night, she receives a visit from Kamijo, who manages to find Misaka's documents about the project. Kamijo catches up with Misaka on a bridge, where he tries to talk her out of doing anything rash.

With the end of summer vacation approaching, the girls plan a study session at Saten's apartment to catch up on homework. Everyone is to bring an ingredient for a potluck stew party, but most have trouble deciding what to buy, leading to some surprises.

Febri takes an instant liking to Saten, and is warm to everyone except for Misaka, much to her chagrin. At Judgment, Uiharu is unable to find any information on who Febri is, so arrangements are made to admit her into an orphanage as a "Child Error."

As Yomikawa takes over investigating the runaway security robots, Konori invites the whole gang out to take in a bath at a bathhouse. On their way home, a number of detours lead them to a confrontation with yet another, much more dangerous runaway robot.