While Voltix rushes to the bathroom, Mattew, has other plans.

Mattew: *looks around* The coast is clear, should I do it?

After considering, he decided to go for it and begins peeing in his pull-up, which lasted for quite a while.

Mattew: Ahh... That's better. *puts a paw on his pull-up, liking the feeling of it*

Meanwhile with Voltix...

Voltix: Gotta go! I hope I can take the onesie and diaper off in time...

Voltix heavily stuggled with undoing the buttons of his onesie and untaping his diaper before he it was too late. He did managed to do it on time and goes on the potty.

Voltix: *relaxes* Made it... but note to self, call Mattew if I want to go here again.

After flushing and washing his paws, he had another few minute stuggle with putting his diaper back on, powdering his rear, and rebuttoning his onesie. 

Voltix: Gah... I hope I don't do this alone again...

Going back downstairs, he goes to see Mattew and check his padding, surprised on what Mattew decided to do while he was stuggling with going potty.

Mattew: Umm... I can...
Voltix: Hey, did you just, pee in your pull-up? The indicator is gone.
Mattew: *blushes* Voltix... I'm quite shy...
Voltix: *giggles*

When does Mattew get changed by Voltix?

1: As soon as the next part begins
2: Somewhere in the middle
3: At the end of the next part
4: Not in the next part but in a future part

Also, the second choice is Mattew's new padding when he does get changed. After this, the next time a design decision will show up will be quite a few parts away.