When the Warumonzaemon bio-emerged, it seemed rather mundane, or as mundane as the emergence of a giant black teddy bear could be. However, thanks to Ruki's mother Rumiko, they'd been delayed: the elder Makino having tried to convince her daughter yet again to join her for one of her modelling jobs. Ruki and Renamon managed to arrive late, just in time to see Growlmon wrap things up.
"A wasted trip," Renamon said.
"Well, it got me away from Mom," Ruki sighed.
As they went back home, they wound up going the direction the Warumonzaemon had arrived from. This meant that Ruki, idly kicking a pebble along the ground, noticed a small golden hourglass lying in a flowerbed, marked with symbols that looked familiar.
"Renamon, is this something from the digital world?" She asked as they examined the find.
"...I think this is something Digi Gnomes use. I'm not sure what they call it but it works like a system restore function for their powers. It lets them allow changes for a short period of time that they can completely undo if they don't seem to be working out well."
"So it might be a good idea not to leave it lying around here?"
"Yes, I think maybe we should look after it until the gnomes come for it."
Back home, Ruki's hope that her Mother had managed to forget about their 'discussion' proved to have been in vain.
"So, everything settled? Good, now, I think this is an important opportunity for both of us..." Rumiko began, barely before they were back in the house.
"Agh! Mom, I don't want to model, all right?! Aren't there girls who do this kind of thing professionally they can hire?"
Renamon sighed.
"I'll just go put this somewhere..."
"Well, yes, but you're my daughter, Ruki. I really wish you could see things from my perspective..."
"And I wish you could see things from mine-" Ruki began, and the golden hourglass glowed for a second.
"-I'm not interested in modell... Wait, what?!" Rumiko finished the sentence.
'Rumiko' looked down at 'Ruki', who looked back up in shock.
"...Did you just manage to swap our bodies with something from the Digimon planet?" 'Ruki' asked.
Renamon looked down at the hourglass.
"Er, you both did, you wished for it and somehow this hourglass actually granted it."
"Well, I wish to undo that wish!" Rumiko said from Rika's body.
Nothing happened.
"Please undo the previous wish?" Ruki-as-Rumiko tried.
"We're stuck like this?!" Rumiko-as-Ruki screeched.
"Wait, calm down, Mom! Renamon, you said the hourglass is only temporary, right?"
"Er, I think so, but it can leave the changes in place for up to a month. Unless they're saved they revert..."
"So it's temporary, but we're still in trouble! My modelling job is this weekend, and I really doubt Ruki's going to manage without me there to help... Aha, you might be modelling anyway now!" Rumiko grinned.
"Uh... - I wish we could swap ages!" Ruki said quickly.
Rumiko's eyes widened in alarm.
"Wait, Ruki, what about-" Rumiko began, only for the hourglass to glow.
In an instant, the redhead was now the taller of the pair, an adult looking down at her blonde daughter. The heart-pattern shirt and jeans had fortunately grown with her, as had the sundress 'Rumiko' wore shrunk along with her own regression in physical age.
"Oh never mind, I was worried I was going to ruin your shirt for a minute."
You could have just repaired it anyway with the hourglass," Renamon pointed out.
"True... Wait, Ruki, how does this help?! I'm just an older you and you're a younger me! If anything it's worse now, if I show up as you they'll not recognise me!"
"Well, that's the next part - I wish we swapped identities!"
The hourglass glowed.
"...Okay, explain."
"Now as far as the world cares, I'm me, and you're you," Ruki grinned.
"I said explain, Ruki, that did not help."
"Oh. Well, this body is now Ruki Makino, even though we both know it's yours aged-down with my mind in it, and you're Rumiko Makino."
"And how sure are you this has actually worked, since Renamon's been standing here the whole time and she knows what happened too?"
"I do, yeah. I remember it all."
"Oh. Where's grandma?" Ruki wondered.
"In her room."
"Good, but first, I wish we swapped clothing and hair styles!"
The hourglass glowed, and the redhead now wore the sundress and loose hair, while the blonde now had the heart-shirt, jeans, and pineapple-head.
On the other side of the Makino house, Ruki knocked on her grandmother's door.
"Ah, hello, Ruki," Seiko greeted her granddaughter.
"Hi, grandmother... You didn't hear anything from the other side of the house, right?"
"No, why?"
"Nothing, nothing... And I've always been blonde, right?"
"Yes... Is something wrong?"
"Oh, no, nothing at all, bye!"
She then left, Renamon not following. Seiko sighed.
"I don't even want to know what's going on."
"It's a long and complicated story," Renamon admitted.
"Which is why I don't want to know."