The Iwatobi Swim Club needs one more member before it can participate in relays.  Nagisa has set his sights on his classmate Rei, who is a member of the track team.  Despite Rei's refusal to join, but Nagisa appears intent on recruiting Rei into the swim club.
That's your reason?
Das ist deine Begründung?
Per questo?
É esse o seu motivo?
И всего-то?