She's a bedwetter

Amity Blight was having a lot of fun with her girlfriend, Luz Noceda.

Luz had invited Amity over to the Owl House for a sleepover, and it was the first she had been invited to in a while. The two took part in a lot of fun games and activities, even trading some close secrets. However, just when it was time for them to get ready for bed, Amity seemed hesitant to do so.

"Hey, are you okay? What's wrong?" Luz asked as she noticed Amity clutching her backpack.

Luz's question only seemed to get to Amity further. "L-Luz? Can I ask you something? Can you keep a secret?" Amity asked. Not even Willow was aware of this, and she had sleepovers with Amity all the time. The fact that Amity was willing to trust Luz with this knowledge said a lot about how much she cared for her.

"What is it?" Luz asked.

Amity took a deep breath and took something out of her bag, a folded white rectangle with a blue stripe down the middle.

Luz seemed to know what her awesome girlfriend's secret was. "Amity, is... is that a diaper?"

All Amity could do was nod shyly.