Kurisu thinks that this is officially the strangest situation she's ever been in. Mayuri had taken Okabe aside, chatted with him for a couple minutes, and then gathered her and Daru to explain what was going on. "What do you mean he's ten years old!" she burst out, looking at Mayuri incredulously.
Mayuri shushed her almost impatiently, and responded, more quietly, "He only remembers stuff from when he was ten."
"So he has his ten-year-old mind in his present-day body?" Daru asked. "This still sounds like a really bad prank."
Mayuri crossed her arms. "It's not a prank, and he's not lying. I can tell." She thought for a moment, before asking the question that was on everyone's minds. "What are we going to do?"
Kurisu, still in disbelief about the situation, finally spoke again. "Well, you said that you're sure he's not making this up. So, if he's currently a ten-year-old trapped in a twenty-year-old's body, then we should probably figure out how this happened, and how to fix it." She doesn't understand how Mayuri can be so sure, but since she's their resident Okabe expert, she decides to just go with it.
"How could something like this happen?" queried Daru, looking puzzled.
Kurisu bit her lip and ran her fingers through her hair, thinking. Finally, she voiced her thoughts. "Maybe it's an after effect of his time travel experiences? I honestly have no idea. And I know even less about how to fix something like this. I'll try to think of a solution. While I do that, we should probably keep him here." Another thought occurs to her. "And we should probably try to avoid telling him too much about the future. Who knows what kind of consequences that could have."
"You mean we have to keep Okarin in the dark about all this?" Mayuri asked, upset. "That's not a very nice thing to do."
"I'm sorry, but I think it's for the best that he doesn't know everything about his future yet." Kurisu responded, hoping to placate Mayuri.
"Fine," Mayuri acquiesced, but she didn't sound very happy about it. "I'll keep Okarin busy while you two figure this out." She stood up and walked over to Okabe, who was sitting on the couch where Mayuri had left him, staring around the lab in confusion.
"This is going to be fun," said Daru sarcastically. "Where do we even begin?"
Kurisu and Daru take up residence at the whiteboard next to the couch, attempting to brainstorm a solution to their very unusual problem. While they work, they can hear Okabe and Mayuri's quiet conversation.
"When did I get so tall?" Okabe asks Mayuri. His voice is quiet, almost as if he's afraid of it.
Mayuri giggles. "Isn't it amazing?" she grins. "I mean, you were always taller than me, but once you turned sixteen you just kept growing!"
Okabe laughs with her, then goes quiet for a minute. After a minute, he asks, "Who are those two?" He gestures to Kurisu and Daru.
"Oh, right, I forgot to introduce you! That's Hashida Itaru," she explains, gesturing to Daru. "Or Daru, which is what you and I call him." She points to Kurisu. "And that's Makise Kurisu. They're our friends!"
Okabe stares at Daru and Kurisu for a moment before replying. "They're our… We have friends?" he asked, sounding absolutely astonished.
"Yep!" Mayuri chirped excitedly. "Mayushii is so happy! You don't have to be so lonely anymore!"
Okabe considers that for a moment. "Mayuri, I'm never that lonely. After all, I have you."
Mayuri seems to freeze for a moment. Finally, she responds in a very small voice, "Thank you, Okarin."
Later that evening, after Mayuri makes dinner and Okabe has fallen asleep on the couch (apparently having your mind jump forward ten years is exhausting), they gather around the microwave to discuss a plan of action, keeping their voices low.
"Well, Daru and I have pretty much worked out that it must be an after effect of the time travel," Kurisu begins. "If he could disappear from this worldline, then it seems reasonable that something like this could happen. Unfortunately, we still have no idea how we're supposed to fix this or undo it."
"On another note," Daru interrupts the conversation. "What's going on with Okabe? Why is he so quiet?"
"It could be because of trauma from the mind switch," Kurisu hypothesizes. "He could be in shock."
"There's nothing wrong with Okarin," announces Mayuri.
"How can you be so sure?" Kurisu ponders the possible consequences of time travel and switching minds with one's younger self. "Who knows what time traveling could have done to him?"
"He's not acting strange," corrected Mayuri. "He's acting perfectly normal."
"But he's so quiet, and hesitant, and he hasn't done an evil laugh even once," argued Daru. "That's not normal for him."
"He's ten years old. This is how he acted when he was ten," Mayuri points out. "Okarin will be fine," she assures them.
"I've got to go home," says Daru, now that the issue is resolved. "May, you should probably head home too."
But Mayuri just shakes her head. "I can't go home. Who's going to stay with Okarin if I leave? I'm going to stay here. I already told my parents."
"But Mayuri, you don't have any of your stuff here," Kurisu points out.
"That's not a problem! Mayushii keeps some clothes and other stuff here in case of emergencies," she explains. "So there's no issue in me staying here."
"I'm going to stay here as well," Kurisu decides. "I'll need to run over to my hotel to grab my clothes, though. We'll try to figure out how to return Okabe to normal tomorrow," She finishes, glancing over at the sleeping figure on the couch.
