In the world, Mastay (Mastay 
) is an extremely rare gender-neutral first name. Much more prevalently, Mastay is the last name as well as the forename.
Amy, Diane, Jerry, Terri, Tyler, Erica, Holly, Matias, Maggie, Sandra, Sierra, Sergio, Andres, Andrew, Rachel, Robert, Dustin, Joseph, Jimena, Thomas, Nickie, Marcelo, David, Derek, Denis, Ralph, Ben, Ken, Tom, Alex, Lisa, Jose, John, Olga, Maria, Marta, Matthew, Marcy, Sarah, Samir, Scott, Chloe, Casey, Brian, Bruce, Keren, Pablo, Pedro, Marlo, and Michael