It is those group of people or a person itself as a new fan of the 5 Seconds of Summer. They pronounce 5SOS as ‘5 es-oh-es’ Usually consider itself a fan after the 5 Seconds of Summer released their single She Looks So Perfect.
5soser: “OMG THE LEAD SINGER IS SO HOT!!11! I AM A 5SOSER NOW1!11!”
av IamGucci 14 april 2014