Morty knows he shouldn't be screwing around with multidimensional shit. It's dangerous, it's impractical, it's blah blah blah. But it's a potential key to unlimited energy, how does nobody see that? He's built a dimensional siphon (it kind of looks like a cardboard box with a funnel and a TI-84 taped to it, but it damn well works), keyed in the dimensional coordinates to a random plane, and by God he's going to use it.
He flips the switch and waits for the energy bar to fill up.
It does! It fills up very rapidly. Then it explodes, along with the box. There's rather more smoke than there should be, and once the smoke clears someone is standing there.
"Whoops?" Morty says faintly.
"Yeah, only seniors get singles. I mean, seniors and Hawthorne kids, but with the Hawthorne kids it's because they might accidentally kill them."
Posters are available in many varieties! Some denote affection for a band or singer. Some are reproductions of presumably famous works of art. Some are just nature scenes or pretty patterns. One is of a cat hanging on to a branch with the caption HANG IN THERE!
Bella takes a nature scene; they're not that expensive. "They might kill their roommates?"
"Hawthorne's the dorm for kids with uncontrolled or otherwise dangerous powers. There's a boy who can't be looked at directly because he drives people insane with his beauty, a little kid who's the involuntary host of an ancient demon, a girl who projects her own emotions so strongly that she gives people aneurysms... It's nasty all around."
"No, they've got specially built containment measures too. But for obvious reasons, Hawthorne rooms are singles."
She will take some candy after reading all the ingredients and some single serve bags of cheese popcorn, for snack emergencies. "Is gum really popular here?"
"I think having way more gum than seems reasonable is just a natural feature of convenience stores."
"If you say so." She doesn't buy any gum. She swings through the aisles to see if anything else catches her eye. "What's that?" she asks of a rack of cell phones.
"Oh, I knew I was forgetting something - those are cellphones. They're like tiny computers that also allow you to talk to anyone who also has a cellphone. They're very useful and you should probably have one."
"Are there also wall mirrors? Big stationary ones on walls so you can get a better view of each other?"
"You can video chat on a laptop? That's the closest thing I can think of. Oh, and phone calls are audio-only - there's ways to send text and pictures but that's a separate thing. You can technically video chat on a phone but I find it kind of annoying to deal with."
"You'd know better than I would! Which of these is easiest to learn to use from a cold start?"
Morty looks through the phones, then picks a model. "None of them are going to be super easy, but this one takes voice commands, so I think it'll make more sense."
"Cool." She baskets it. "I guess I'll have to come back for textbooks later so it's okay if I've forgotten something."
And Morty shows her to Melville so she can drop off her purchases in her dorm room!
"I'm gonna have to leave you here - the Melville housemother or fixer's gonna take over now that you're in their territory. It was nice meeting you! Even given the, uh, circumstances."
"You're welcome and I will hopefully never do it again because that was absurdly lucky!"
He makes his way back to Twain.