Who is Senhor Manuel from Child of the Dark and what is their importance?

Manuel is the man who overpays Carolina for her sack of scraps so that she has enough money to pay her light bill. Later, Carolina asks if he's made a mistake in the opposite direction, underpaying her. She says that he wants to marry her. She speaks well of him, saying that he works hard, never misses a day and is "distinguished." Over the course of the book, Carolina interacts with Manuel often. She says that he sometimes says he's never coming back, but that he does.