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...
I think one of your strengths is being able 
to interpret even small things as positive.
أعتقد أنّ إحدى نقاط قوّتك هي القدرة
على تفسير أصغر التّفاصيل إيجابيّاً
Und deine Stärke liegt darin, jeder noch so
kleinen Sache Positives abgewinnen zu können.
Tomarte hasta las cosas pequeñas
con optimismo es uno de tus talentos.
Tomarte hasta las cosas pequeñas
con optimismo es una de tus cualidades.
Sono sicura che riuscire a vedere tutto in positivo
sia un tuo pregio, Souma.
Acho que a sua força é conseguir ver
até a menor das coisas como positiva.
Думаю, твоя сила — в умении
находить радость в таких мелочах.