Ronaldo is Pepper Saltzman's assistant and later boyfriend. He has mentioned he is from Guatemala, however it is unknown if he was born there or not.
Pepper's ideas though are a little extreme for them and not what they want and when they tell Pepper he feels insulted and leaves. Ronaldo has some ideas that the couple likes very much although they feel guilty to hire him because Pepper is their friend and they don't want to hurt his feelings, and he leaves.
The next day, he returns to the Pritchett-Tucker house, having left Pepper, to explain them his ideas. But when Pepper suddenly arrives, they force Ronaldo to hide, and Pepper is upset for being stabbed in the back and vows to ruin the wedding of whoever is responsible for encouraging Ronaldo to leave.
When he finds out Ronaldo is there, he has a nervous breakdown. He has planned 53 gay weddings, and not a single one of them were for him. Ronaldo is upset for an even bigger reason: he is in love with Pepper and Pepper never even noticed. That's probably because Pepper was too obsessed with planning 53 gay weddings to notice Ronaldo was in love with him.
After a heartfelt conversation, they officially become significant others, and now they are back to planning the wedding.