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.
Why won't you leave me alone...
¿Por qué no me dejas solo si me dijiste que me fuera?
¿Por qué no me dejas solo si me dijiste que me fuera?
Por que não me deixa em paz...