Embarrassing for both

When they got in the bus there were no seats available so they had to grab from the bars of the roof.

Sako was holding her towel with one hand and the bar with the other, she was enduring it pretty well till suddenly the bus took a sharp turn that made her release her grip from the towel that fell at her feet, sako gasped and wanted to pick her towel up but she couldn't because she felt like the bus will throw her if she let's go of the bar.

As for her mom the snagged thread at the bench of the bus stop kept snagged as the bus took off so her skirt unraveled all the way till it was nothing but the waistband, sako's mom was completely unaware of her pink hello kitty panties being exposed to the eyes of everyone in the bus till sako's gasp made her look down just to see her own embarrassing state

Sako's mom face turned completely red but there was nothing she could do so daughter and mom had to endure the bus ride in humiliation.