Is Lucy married to Zeref?
Lucy Heartfilia also know as the dark queen is married to Zeref Vermillion brother of Mavis Vermillion so she is known as Lucy Heartfilia Vermillion. Her and Zeref are 400 years old together they where married at the age of 18.
In which episode Natsu find out he’s Zeref’s brother?
He finds out in chapter 465 from Zeref. He finds out in chapter 465 from Zeref.