Tierno is a tall, heavy-set boy with black hair in a short back and sides that also resembles the leaves on Chespin's head. One of his most noticeable qualities is that he has a rather overweight physique. Even so, this hardly seems to impact his desire to be a dancer. He is shown wearing a large black T-shirt that has a Vanillite design on it, orange cargo shorts, a yellow backpack, and matching black and yellow sneakers. Tierno also wears a yellow watch with a black wristband.

Tierno is a friendly guy, who aspires to become a dancer. Tierno sometimes gets inspiration for his new dancing moves from his Pokémon, Corphish and sometimes uses his Roller Skates to improve himself. This also allows Tierno to develop certain strategies, both in battles and outside them.