"August 20, Part 1" (八月二十日① Hachi-gatsu Jū-ku-nichi ①?) is the 31st chapter of the Toaru Kagaku no Railgun manga series.
The chapter opens with Touma losing 2000 yens to a vending machine; Mikoto pushes Touma out of the way, slightly blushing. Touma, after going through his amnesia, forgets who Mikoto is and she attacks him. Mikoto does her 'One, two chaser', kicking out a can out of the vending machine.
Both Kazari and Saten meet up with Kuroko who's in despair. Worrying, over Mikoto, Kuroko describes her problem to the pair, to which Saten suggests Mikoto's strange behaviour is due to a boy (Although, really, it was the 'Sisters Project' that had her perturbed). Letting their imaginations run wild with the reason behind Mikoto's late returns to her dorms, Kuroko hears an alarm for a vending machine and she teleports to the vending machine.
Touma is seen running away from Mikoto, who is concerned he'll become an accomplice to a crime by taking Mikoto's cans. He accepts anyway and Mikoto vaguely describes their fight around town, to which an amnesia riddled Touma interprets as love, rather than violence. Kuroko runs around the corner to see Mikoto and Touma on a seat and instantly interprets that they are a couple (Much to her dismay). Introducing herself as Mikoto's "Only friend", she makes a snide remark about Touma being easily attracted to other women, to which Mikoto attacks, asking "[Does] this weirdo look like my boyfriend?!". Kuroko teleports away, seeing that Mikoto is once again in lively spirits.
Behind Mikoto, Misaka 10031 calls out her name, much to her shock. Mikoto pulls her away from Touma and questions MIsaka 10031 about the project's status, to which Misaka 10031 replies that it is continuing. Mikoto is shocked, feeling guilty about the death of the sisters and recalling the last one that died in front of her.
Mikoto physically feels sick, as she supports herself on a light-pole; Misaka 10031 calls out for her attention to another cat, recalling the last Misaka's interaction with a cat, and this causes Mikoto to shout at Misaka 10031 to stop appearing before her, remembering the last Misaka. Misaka 10031 looks shocked and walks away, following Mikoto's instructions. Mikoto weakly calls out for her and the chapter ends with Mikoto semi-collapsed on the light-pole, in a state of despair.
- Touma is officially reintroduced to Misaka Mikoto after losing his memories.
- Parts of chapter adapted from Toaru Majutsu no Index Light Novel Volume 03 Chapter 1 Part 1-2
By order of appearance:
- Electromaster - Misaka 10031
- Mikoto and Touma's first meeting is referenced by Mikoto, as well as their fight in the artificial riverbank.
- In the background while Saten Ruiko and Uiharu Kazari walk by a shop, the unnamed Judgment Boy and the Twin Tails Girl he saved back in Chapter 4 of Toaru Kagaku no Railgun are seen together in casual cloths on a date.
- In Japan, 2000 yen notes are actually exceedingly rare. When introduced on July 17, 2000 to commemorate both the new millennium and the G8 summit held in Okinawa, the 2000 yen note was the first Japanese denomination to have a primary numeral that was not 1 or 5. Though still in circulation, the 2000 yen note never caught on, partly because of this unusual distinction (to Japanese eyes) and the fact that many vending machines won't accept them. It could be said that, when Touma fed the machine with that bill, he was probably tempting fate.