Yuta Hibiki wakes up in the home of his classmate, Rikka Takarada, with amnesia. A voice from an old computer, identifying himself as "Gridman," has a mission for him, but can he even survive the next day of school without his memories?
does that mean you don't remember
anything that happened today?
dann weißt du gar nicht mehr,
was heute passiert ist?
¿no recuerdas nada de lo que sucedió hoy?
T’as aucun souvenir d’aujourd’hui ?
significa que não sabe 
nada do que aconteceu hoje?