Almost two weeks pass. Sadde still has work, even if school's out, but they and Theo hang out a bit more. No new cards appear, and Kero seems to not think that strange, so Sadde themself doesn't care. And one day Theo gets a text in the morning: Happy birthday!
Sadde falls on his haunches, and stares at Theo's retreating form. He scrambles to his feet and runs after Theo again.
Theo looks back, notices Sadde's still following, and speeds up. Apparently he can control his superspeed in some scenarios.
Theo has indeed gone. He's gone for quite a long way and has found a deserted space to hide away where he can get okay again.
Which Sadde predictably can't find.
Theo gets a text: I'm sorry. Please don't be mad at me.
He walks past his dad, making a half-hearted effort to assure him he's fine, then goes to his room. He assures Kero he's fine.
He stays there all throughout Tuesday.
And Wednesday.
He does go to school Thursday, though.
Kero is neglected during those days. He has to actually go to the kitchen on his own to get sweets!
Sure! You wanna come over here?
It might be implied that Theo wouldn't want to go out again, not just yet.