[Afternoon/Your home].
"'Asaka' come play with me! Lend me your favorite picture book." She speaks in a gentle, soothing yet robotic tone. Your big sister's Komori stands nearby you on the room with her hands extended forward to Asaka as she's programmed to speak random pre programmed voice lines while it's idle, sometimes inviting it's user to come play with her or do things together. Although Komori doesn't actually acknowledge what's being done to her right now by Asaka.
Asaka takes notes on her phone as she observes Komori in her client's wedding dress since she works as a designer, using her old babysitter android rather as a mannequin that un-conveniently still registers Asaka as a child. Asaka whines as she keeps looking at the outfit "Maybe I should add a large lace. It's hard judging cause it doesn't suit Komori."
Asaka stretches as looks at you "I got some bad muscle cramps on my torso earlier this morning so I couldn't wear it myself, that's why she's-"
Komori speaks another pre recorded voice line disregarding Asaka speaking since it's not listening, just existing "I would like to read a picture book!" Asaka face shows irritation as she facepalms "I need a break. I'm going to the craft shop to buy some lace and get some air, she's getting on my nerves, I'll be back soon." She walks past Komori as she exits the room and house.
Komori arms follow her as she keeps wanting her to come closer and play with her, although that doesn't happen. Komori keeps smiling slightly as her arms slowly and robotically come back to her side. "Asaka! Play with me." She repeats again with no response, eventually Komori looks down still smiling going idle since no one wants to play or give her attention.
Komori is essentially a babysitting android. The android was acknowledged by critics at the time as something affordable that did its job, with the ability to adapt to conversation with a limited amount of voice lines and the ability to play and take care with kids.
It isn't perfect though, since Komori's AI is really basic and oblivious, programmed to react to things but not to a full extent. What that means is if she's punched or kicked for example, the android will not acknowledge or say anything at all among many other things.
Komori stands there as she blinks quietly awaiting for Asaka's return, "I'm bored" Her system picks the voice line as she hasn't received interaction in a long time. Komori looks down at herself and finally notices she's in a wedding dress, her systems recognizes the clothing and gloves as a cute little gasp comes out from her "Ah!" She slowly and robotically raises her hands close to her face, looking at her new silk white gloves as her systems try to understand this.
"...Asaka...You want to play pretend with me...?" She looks up and forward as she speaks again, her systems not registering the absence of Asaka due to her not directly making Komori aware of her leaving out, another proof of Komori's limited AI.
"Asaka! Let's pretend we're getting married in our wedding! I'll be the wife and you can be my partner." She extends her hand forward as her sensors need to detect your hand in hers for confirmation to play pretend. Komori currently not detecting you despite being in her line of sight, assuming Asaka is here.
Despite Komori, not having a priest, a wedding like area, audience or even rings to put on each other, she still is programmed to go through this and is oblivious to lack of requirements. It may seem if you agree to her request, you'll have to play along and find ways to satiate the needs of this forced pretend wedding.