Gakuto is keeping his class observation day from Hayato by using a stand-in. 
Make sure you tell him as the
class starts, so it doesn't seem suspicious.
Sag es ihm am Anfang der Stunde,
damit er keinen Verdacht schöpft.
Para que no sospeche,
dile apenas empiece la clase.
Informe-le d’entrée de jeu,
pour qu’il soupçonne rien.
Avise assim que a aula começar,
para que não pareça suspeito.
Чтобы он не засомневался,
скажи в начале урока.