Rey was born and raised in Pampanga, a province in the upper island of the Philippines. He began his music career when he was in third grade as a boy soprano in a religious group called Mirabilia Dei, which has a mission of spreading the word of God through church music. There, he began his music studies focusing in singing and solfege.  In 2007, the group had the opportunity to learn stringed instruments. Rey first wanted to learn the violin but he was asked to learn the cello instead. With the generosity of Sr. Mary Placid Abejo, OSB, some members of the group, including Rey, were granted scholarships for college. He enrolled at St. Scho School of Music, St. Scholastica's College - Manila for a Bachelor of Music in Music Education degree.

When Rey auditioned for St. Scho, cello was his principal instrument, however, he was encouraged to shift to the Double Bass for a full scholarship. Rey accepted the offer, and so he began his Double Bass studies at seventeen with Rommel Cruz, bassist of the Philippine Philharmonic Orchestra. Rey completed his undergraduate studies at St. Scho in 2017, earning a Bachelor of Music in Music Education with Double Bass Principal, and received the Sr. Baptista Battig Award. While at St. Scho, he was the recipient of the Sister Baptista Battig Music Scholarship, Philberth Scholarship, and Future Faces Manila Scholarship. Graduating magna cum laude, Rey holds the title of the very first male valedictorian of St. Scholastica's College - Manila and is recognized as the institution's first ever Double Bass graduate.