Declan had wavy, dark brown hair that fell just above his shoulders. He had piercing green eyes and a charming smile along with dimples. He stood at 6 feet tall with a lean and toned physique. He had a few tattoos on his arms and chest, adding to his edgy and cool appearance. He was mostly often seen wearing a leather jacket and ripped jeans, giving off a rocker vibe.

Declan was charismatic, confident, and passionate. He had a natural stage presence and loved performing for his fans.