Mahiro and the Girls' Day Out

Mahiro and the Girls' Day Out (まひろと女の子の休日, Mahiro To Onnanoko No Kyuujitsu) is Chapter 9 of Onimai: I'm Now Your Sister. It was originally published on Pixiv on October 28, 2017.

Summary
When Mahiro and Mihari go to the mall to see a movie, they run into Kaede and go shopping.

Plot
An advertisement for a new film My Name plays on the Oyama's television, being called "the single greatest work this century". Mahiro is excited about it finally being out, and says that she can't wait for it to be on streaming.

Mahiro says that she almost wants to see in theaters, but says that it would be tough for an "own-home security guard" like herself. Mihari admits that she actually wants to see it as well and suggest that they see it together, much to Mahiro's shock. Mahiro is left feeling ill at the thought of having to go outside to see it.

Later on, Mahiro hides behind Mihari as they travel through a shopping mall; Mahiro is upset as she thought that they were only going to a movie theater. Mihari explains that the top floor of the mall is a movie theater. Mahiro cringes again, remarking that this lively atmosphere is hazardous to her health. Mihari tells her not to be so melodramatic.

Mahiro gets overwhelmed and starts pulling on the skirt of Mihari's dress saying that she can't do it and that they have to leave now. Mihari is shocked and tells Mahiro to stop doing that, hitting her on the head to make her do so.

Just then, a voice calls out "sorry I'm late". It turns out to be Kaede, who says hi to them. Mahiro is suprised to see her, and Mihari explains that she invited Kaede in secret. Kaede hugs Mahiro from behind telling her that it is good to see her again. Mahiro feels the same way and forgets all about wanting to leave, making a cutesy expression. She then comes to her senses, realizing that she accidently made a cute noise and gets a bit freaked out about it. Kaede asks what it up with Mahiro, and Mihari thinks to herself that Mahiro is having a flashback to her head-trauma personality.

Kaede then says that they should go shopping, Mihari agrees to it, while Mahiro is a surprised. Mahiro tries to point out that they came here for the movie, but Mihari points out that they actually have some time to kill before the movie starts. Mahiro cringes, realizing that she was tricked. Her fears are a bit assuaged though when Kaede says that they should enjoy their "date".

The three girls go off an do a load of fun things. They shop for jewelry at one store, with Mihari and Kaede noting how cute it all is. Mihari tries out a cap with a set of glasses. Kaede even has Mahiro try on a flower necklace and puts a large flower beret in her hair. By the end of it all, Mahiro is exhausted, noting that shopping as a girl is tough.

Kaede notices that Mahiro is worn out and suggests that they take a break on a nearby bench. Before they can, she sees a sign above the bench advertising a swimsuit sale on floor 3F. Kaede beams with joy, saying that she forgot that she needed a new swimsuit. Mahiro cringes at the thought of more shopping.

At the swimsuit store, Kaede remarks that she is a sucker for whatever is in style. Mihari remarks that she doesn't think that she has worn a swimsuit for anything but gym class since middle school. Kaede is shocked at this, remarking that it is terrible. Mihari points out that they never went to the beach as she was in track. Kaede subsequently drags her to the changing rooms remarking that she'll just have to try on one now and says that se'll try one on as well.

As the girls get changed, Mahiro is amazed at how excited they are at this, then realizes that Kaede said "try on on".

Kaede pulls back the changing curtain saying "ta-dah", revealing her wearing a gorgeous skimpy two piece the shows off her mature womanly curves in all the right places. Mahiro is shocked at how good she looks. Kaede bends over and asks Mahiro what she thinks, placing her bust directly in the path of Mahiro's eyes. Mahiro is amazed at how stacked Kaede is, leaving Kaede feeling a bit embarrassed. Mahiro makes a prayer thanking god for shopping.

Kaede calls out to Mihari, and Mihari reluctantly pulls back her curtain. Mihari, slightly embarrassed, shows off a two piece bikini with a skirted bottom and asks how she looks. Mahiro's blank expression doesn't change this time, admitting to Mihari that she has some stiff competition in Kaede. Mihari, now very pissed off, remembers that Mahiro said the other day that she wanted a swimsuit. Mahiro freaks out over remembering that, and Kaede decides to help with that, despite Mahiro's attempt to explain.

Kaede has Mahiro try on a skimpy yet extremely adorable bikini with a ruffled top, much to Mahiro's embarrassment. Mihari beams with pride, remarking that Mahiro is adorable. Kaede also comments that Mahiro is super cute. Mahiro then pulls the curtains shut and decides that she's had enough, with Mihari disappointingly calling her a tease. Mahiro asks if they are kidding and says that she can't let anyone see her like this. She says that it is like she is in her underwear, and Mihari decides that Mahiro has a point there.

Kaede also agrees, saying that she guesses that anyone would be embarrassed like that wearing their first bikini. Mahiro feels better hearing Kaede say that. Mihari suggest trying on a one-piece swimsuit then, with Kaede suggesting that they could also look at wraps. Mahiro ultimately feels overwhelmed once again by this.

Soon after, they leave the store with Kaede remarking that Mahiro now has the swimsuit she wanted. Mahiro laughs along at the joke, but wonders what she is even going to do with it. Mihari notes that she ended up with one as well. Kaede then realizes that she feel like they forgot something. Mihari looks at her phone and realizes that the movie has already started. Mihari pushed them towards the theater remarking that it is Kaede's fault for having them try on swimsuits, to which Kaede apologizes.

Ultimately, they fail to make it on time and Kaede asks if they want to wait for the next showing. Mihari is exhausted and suggests that they instead meet up again next week. Mahiro cringes but agrees as long as there is no more shopping.

Later at home, Mihari has Mahiro try wearing her new bikini in their bath. She snaps a picture of Mahiro while she's doing so, much to Mahiro's shock.

Characters

 * Mahiro Oyama
 * Mihari Oyama
 * Kaede Hozuki

Trivia

 * The movie My Name that Mahiro, Mihari, and Kaede go and see is a parody of the acclaimed 2016 anime file Your Name.
 * Mahiro references when she gained a younger personality in "Mahiro Starts Over".
 * Mihari references what Mahiro previously said in "Mahiro and the Gatcha Game", though out of context.