Mahiro and the Photo Albums

Mahiro and the Photo Albums (まひろとアルバム, Mahiro To Arubamu) is a bonus chapter of Onimai: I'm Now Your Sister!. It was originally published exclusively in Volume 6 of the manga which was released on April 22, 2022 in Japan, and October 25, 2022 in North America.

Summary
Mahiro and Mihari look through their old photo albums.

Plot
Mahiro and Mihari look through the old photo albums that they discovered recently while cleaning. Mihari notes that there is nothing like physical photographs. Mahiro notes that these days pictures just end up stuck on a computer somewhere, with Mihari noting that their mom always insisted on actual photos.

Looking at a photo of the two as shildren with their mom, Mahiro asks Mihari how long their mom is supposed to be overseas. Mihari says that she doesn't remember, but adds that they do text a lot. Mahiro notes that there will be a problem if their mom comes back with her like this, and Mahiri laughs at how true that it.

Putting that aside, Mahiro asks Mihari if she's lonely without their mom around. Mihari is surprised at that statement, pointing out that she's not a little kid anymore. She also points out that she has Mahiro, which Mahiro notes is embarrassing.

Mahiro notes that there aren't many photos of her in recent years, before she was transformed into a girl. Mihari points out that there's a reason for that, and Mahiro remembers it. She says that at the time she wanted to distance herself from adolescent woes. She had an inferiority complex about Mihari, couples with repeated test failures and being weak psychologically.

Mahiro notes that she's sure that in all that time that their mom was missing her. Mihari agrees but tells Mahiro to look at something on her phone. She brings up that she has lots of pictures of "Mahiro-chan", the girl. Mahiro is interested and asks to see them.

Mihari shows Mahiro a picture from the first day. Mahiro laughs and notes that she was so innocent then.

Mihari then shows a cute photo of Mahiro in a cat costume, which Mahiro remembers was on Halloween.

Mihari then shows a picture of Mahiro relaxing during their trip to the hot spring, which Mihari remembers as being a lot of fun. Mahiro notes that she was scared half to death.

Mihari then shows a picture of Mahiro wearing her uniform on her first day of school. Mahiro notes that she never imagined that she'd end up in junior high again.

Mihari then shows a picture from their date when they went to the Onimaen amusement park, and notes that she's going to cry over such a happy memory. Mahiro angrily tells her not to call it a date.

Mihari then shows a swimsuit pic from the recent trip to the beach. Mahiro freaks out about it, while Mihari notes that there's a lot more of Mahiro outside these days.

Mahiro notes that looking back, a lot has happened over the last year. Mihari is touched and notes that Mahiro has finally gotten a life off the internet. Mahiro insists that her inner "own-home security guard" is still alive, but Mihari asks what is wrong with having a life. She adds that she has all the photos backed up, noting that it would be a shame if they got deleted. Mahiro notes that that is the trouble with digital, and says that they could always get some of them printed too.

Mihari notes that that is true, and decides to put together a new photo album with all these pictures. She suggests that they call it "The Mahiro-chan Growth Record", which Mahiro refuses imaging that name to be more fitting for a baby. Mihari suggests that they work hard to add more pages to it, and Mahiro admits that it's not so bad.

Mihari tells Mahiro that they'll start by assembling the cutest pics, and says that if Mahiro has any selfies she likes to send them to her. Mahiro refuses, telling Mihari that she's not sending her anything.

Characters

 * Mahiro Oyama
 * Mihari Oyama
 * Mrs. Oyama

Trivia

 * Mahiro and Mihari look through the photo album that they discovered in "Mahiro's Deep Clean".
 * Mihari's photos of Mahiro reference the events of several previous chapters:
 * "Mahiro's Confusing New Body" - When Mahiro was first transformed into a girl.
 * "Mahiro Attends a Party" - When Mahiro wore a cat costume to a Halloween party at Kaede and Momiji's house.
 * "Mahiro's Panic! At the Hot Spring (Part 1)", "Mahiro's Panic! At the Hot Spring (Part 2)", and "Mahiro and the Comrade's Return" - When Mahiro and Momiji went on a trip to a hot spring with Kaede and Momiji.
 * "Mahiro's First Day" - Mahiro's first day attending middle school as a girl.
 * "Mahiro and the Gifted Experience" - When Mahiro brought Mihari to the Onimaen amusement park as a birthday present.
 * "Mahiro's Beach Fun (Part 1)", "Mahiro's Beach Fun (Part 2)", and "Mahiro and the Squishy Thingie" - The trip that everyone took to the beach during summer vacation.
 * Based on the statements made by Mahiro in this chapter, it has been roughly a year since Mihari's experiment began in "Mahiro's Confusing New Body".