Shun's younger brother Fuyuki and his girlfriend Mamiya-san kissed.  When Shun finds out, he asks his friends what he should do as Fuyuki's older brother.
Fuyuki ignores his brother and goes on a date with Mamiya.  The gang decides to follow the couple on their date and end up at a karaoke box.
Studying, huh?
¿Estudiando, eh? me pregunto que están estudiando.
¿Estudiando, eh? Me pregunto que están estudiando.
Estudando, é?