Hayate is forced into a situation his only viable option is to do something illegal, unethical, and unbecoming.  After being called a Mom like figure to Nagi, Maria goes to the source on information regarding Nagi’s father.
You can sing, but I'm not 
giving you any money!
¡Aunque cantes no te daré nada!
Aunque cantes, no verás un duro.
Mesmo que você cante, 
eu não vou te dar dinheiro!