Lex, whose full name is listed as Ivez Lexandrei Reyes Santos, is A-ON’s leader. Public introduction posts describe him as someone who leads with intention and performs with purpose, giving A-ON a steady and disciplined center.

Before A-ON, Lex was part of ECLYPSE and was also associated with Top Class. His earlier public profiles list him as a vocalist, dancer, and rapper, making him one of the group’s all-around performers. His birthday is listed as October 29, 1998, but this should be marked as unverified unless confirmed by A-ON or Horizon Digital Management.