"I Don't Know If I Should Carry Out My Duty" (私でお役にたてるかわかりませんけど Watashi de o-yaku ni Tateru ka Wakarimasen kedo?) is the fourth chapter of Toaru Kagaku no Railgun Gaiden: Astral Buddy, released on July 27, 2017. Hokaze Junko goes outside of the School Garden for help regarding her predicament.
Junko and the ghost girl visit the third Judgment Branch office for help with the drawing of the ghost girl she obtained earlier from Misaki. Kuroko mentions that there have been many strange incidents as of late and have been understaffed. After some arguing, Kuroko gives Komaki the duty in investigating the picture.
Junko then asks Kuroko if she knows anyone who is good at investigating things and gathering information. Kuroko has one person in mind. Junko goes to Sakugawa Middle School and surprises the students and faculty there. Junko eventually gets to Judgment 177 Branch Office and meets Uiharu Kazari, who is enamored by Junko's ojou status. Getting back to business, Junko shows off a photo of the drawing, which troubles Uiharu as it would've been easier if it was a photo of the person of a drawing. Suddenly, Ruiko appears and offers her help, much to Uiharu's dismay as she isn't a member of Judgment. Junko mentions to Ruiko of the 7 mysteries of Tokiwadai as it is somewhat connected to the person she is looking for. Junko is ecstatic as Ruiko mentions several rumors regarding ghosts, including a few ones related to the Imaginary Number District.
They then talk about a tree in Tokiwadai that blesses lovers but the conversation turns awkward when they realize that the only people in Tokiwadai including the staff are female. Sensing the implication, both Junko and Ruiko become embarrassed, with the former remembering the few awkward situations she had with fellow female students in Tokiwadai. Ruiko later mentions to Junko about the Indian Poker and invites her to visit a shop that was selling them, while Kazari takes a look at the picture Junko brought.
As Ruiko goes on her "date" with Junko, Keitz Nokleben is with Misaki, being ordered to investigate how Indian Poker is being distributed. Keitz notice Misaki being down, to which Misaki mentions the incident of the monkey stealing her bag. Keitz picks up that Misaki obviously knew who was behind it, which she confirms. In Misaki's thoughts however there is something amiss with the card she has as she could not read the information on the card, though she does sense a powerful malice.
- Hokaze Junko and the ghost girl meet Uiharu Kazari and Saten Ruiko, and receive help from them.
- Shirai Kuroko
- Hokaze Junko
- Ghost girl
- Makigami Komaki (Named debut)
- Uiharu Kazari
- Saten Ruiko
- Keitz Nokleben
- Shokuhou Misaki
- Tokiwadai Middle School
- Sakugawa Middle School
- Judgment 177 Branch Office
- The unnamed Anti-Skill science teacher introduced in chapter 12 of the Toaru Kagaku no Railgun manga is shown to be the science teacher of Sakugawa Middle School in this chapter.
- Saten mentions a couple of rumors, that have been confirmed to exist, about the Imaginary Number District, the first: the City of Shimmers, and the second is Kazakiri Hyouka, the transfer student who turned out to be a "ghost'.
- Junko's near-kisses with other female characters from Chapter 1 and Chapter 3 are referenced.
- As the Indian Poker merchant is still able to sell Indian Poker cards, this chapter takes place before Chapter 77 of Toaru Kagaku no Railgun wherein Misaka Mikoto and Kinuhata Saiai bought of all his cards to get the Bust Upper. Moreover, the fact that Junko has yet to try out an Indian Poker card herself implies that this chapter occurs before Chapter 71 of Toaru Kagaku no Railgun, where Junko gives Misaka Mikoto an Indian Poker card to try out.
- Saten somewhat mimics Tsukino Usagi's iconic pose from Sailor Moon.
- What were the strange incidents that Kuroko mentioned?
- Who was behind the monkey stealing Misaki's bag, and how did Misaki know?
- What is within the Indian Poker card that malice?
- Misaki: "Something bothers me about this. Unlike the others...I can't read the information on this card. The only thing I can sense... is a powerful... malice."--regarding the Indian Poker card she has.