Souma is really susceptible to cracking up, and even memories will put him into laughing fits. But being self-conscious about this, he always tries to hide it. When he does this again at a clothing store his friend works at, the friend asks him why he does that, especially when it's so easy to tell anyway. Later, Shun also repeats the same sentiment...
What's that, you're planning 
a trip to the beach?
ماذا، ماذا؟ هل تخطّطان لرحلة إلى الشّاطئ؟
Hab ich richtig gehört,
ihr wollt ans Meer?
¿Qué? ¿Irán a la playa?
¿Qué? ¿Vais a ir a la playa?
Vous allez à la mer ?
Come, come, andate al mare?
Opa, estão planejando
um passeio na praia?
Вы что, собрались на пляж?