The hem of her skirt

The loose thread was on the hem of Akari’s skirt, on the back. If anyone saw it, they could simply reach out and gently pull on it, which will make Akari’s skirt unravel.

If that happens, it’ll be humiliating for Akari. Especially with the kind of panties she’s wearing right now. The panties Akari was wearing today was her cute silly frilly white undies with a pink little bow on the front and little cartoon bear prints all over them. It would be very humiliating for Akari if her friends see them.

Akari keeps on focusing on what the teacher is saying. But unknowingly to her, someone notices the loose thread on her skirt. And that person is.....