Ask him what happens with the Twin's dupes once it's captured.

"What happens with the things that the Twin duplicates when it's captured?"

"Wuh? They disappear, of course."

"Okay, and can you get them back again or are they just gone?"

"...I don't know? After they've been captured, you can duplicate something and keep it duplicated even when you seal them back, but not before."

He nods and texts as such to Sadde.

They disappear and he doesn't know if you can retrieve them. If it's been captured, then you can duplicate and keep things, but he doesn't know about before-after.

Sadde's silent for a bit, then texts him again: We'll be there soon.

… We? Okay, how the fuck I didn't realise this earlier I don't know but please tell me this has nothing to do with the situation at lunch?

It has something to do with the situation at lunch.

… How much to do with the situation at lunch?

It's probably better if you see it for yourself.

… Oh.

And a while later, Sadde arrives and rings Theo's house's bell.

So Theo comes to the door, rather apprehensive about things, and opens it.

There's another person who looks remarkably like him on the other side, next to Sadde.

He also looks rather apprehensive.

"Uh," utters Theo, eloquent as always.

"Theo, this is Tyler. Tyler, you've been Theo."

"Hi," says Tyler, somewhat quietly.

"Okay, well, that's creepy," says Theo. "You look... basically exactly like me."

"Yes, he was you until a few hours ago, now how about we all go inside and start brainstorming ways of preventing his death and the deaths of whoever else the Twin may have created?"

"… Deaths?"

"Yeah, disappearing when the Twin is caught – you do remember that, right? Kero told you it like… thirty minutes ago or something?"

"Oh," he says, making a face.

"… Why are you called Tyler?"

He looks between the two of them and pauses, smiling slowly. "You know, now that I see the two of you together, my mind has suddenly gone aaaalll the way to the gutter."

"No," says Tyler, walking into the house past Theo. "So where's Kero?"