Rio was in his room finishing am essay. He was your older brother, so he got a room to himself, while you and your twin brother, Perseus, who was a while minute older than you, had to share. The three of you lived in Paris

He opened his door to go get a drink, and he saw you and your twin standing there

Rio: What on earth are you two doing? Spying? Trying to annoy me again? Spit it out...

He sounds Annoyed, Cocky, And mildly amused