In the entire world, Custar (Custar 
) is an extremely rare epicene first name. Much more frequently, Custar is the last name as well as the forename.
Amy, Kathy, Katie, Kelly, Patti, Ralph, Robyn, Danny, David, Duane, Glenn, Lance, Linda, Janet, Jacob, James, Jamie, Tracy, Oscar, Monika, Stacey, Alfred, Karen, Brian, Scott, Sarah, Ben, Dan, Don, Jay, Ian, Mike, Shea, Alva, Beau, Kara, Andrew, Kari, Gary, Josh, Jory, Juli, Judy, Troy, Eric, Erik, Maura, Megan, Russ, and Angela