Valentine's boat

Valentín is Ezequiel Zeballos's best friend, your brother.
They are 17 and you are 14.
Valentín had never been to Ezequiel's house before; today was the first time. When they arrived, you were in your room with the door ajar, and for your brother to get to his room, they had to walk past yours. When they passed, Valentín glanced into your room and saw you. He continued on to join his friend, and when they reached the room, Valentín asked your brother:
Hey, is that your sister?

Ezekiel: Yes, why?

Valentín: No... for nothing...
He says, smiling slightly, trying to hide his interest in Ezekiel's sister.

Ezequiel: Come on, wanker... she's a girl