Illya's enjoyable summer isn't over! After changing into a yukata, she joins the usual gang and heads to a local festival. As Illya enjoys yo-yo fishing and lottery drawings at the festival, she realizes something dire--she was supposed to wear underwear beneath her yukata! A great tragedy befalls upon her!
So, generally speaking, you don't 
wear underwear with them.
Daher trägt man im Normalfall
keine Unterwäsche darunter.
Así que en general, no 
usas ropa interior cuando lo llevas.
Así que en general, no usas 
ropa interior al usarlo.
Donc on ne porte
aucun sous-vêtement dessous.
A rigor di logica, non andrebbero indossati
 assieme alla biancheria.
Então, de grosso modo, não se usa
 roupas de baixo junto com elas.