Rosa is a very caring and loving person, and is always thinking of her loved ones. She is always happy to cook for her family, but can go overboard, and if someone simply wants a snack, she will prepare an entire meal for them. She is also vigilant about her loved ones' health, and will always be prepared with any old remedy she knows to make them feel better.
She is very superstitious as she depends on lucky talismans and assumed that Ronnie Anne was turned into a rat by black magic. She is a very overprotective grandmother, and ready to spy on her grandchildren and track them in case something bad happens.
She is a short, round Latin American woman with tan skin, dot eyes, short black hair, rolled into a bun, and golden circular earrings. She wears a navy blue dress, with a white collar, as well as having white on the end of the sleeves, a greenish blue apron, and black shoes.
She has some similarities to Lucy. They both pop up out of nowhere, and frighten someone without them knowing of their presence, and they seem to know about spirits. The only difference is that while Lucy enjoys (the evil) spirits, Rosa prefers to keep them (the evil spirits) away.