Viejo Cezal serves as Sebastian's adoptive grandfather. He offers Sebastian a home in a Pyrenees mountain village, sharing responsibility for the boy's upbringing with the boy's aunt, Angelina. This arrangement began after Sebastian's Roma mother left him in their care, adhering to her people's laws concerning children born outside the community.

Within the household, Viejo Cezal provides a kind and stable presence. This steadiness contrasts with Angelina's stricter and sometimes more volatile approach to parenting, especially regarding Sebastian's deep longing for his birth mother. He acts as a nurturing and understanding parental figure for Sebastian.

Viejo Cezal fulfills a supportive role in the family structure. His presence anchors Sebastian's foundational environment prior to the boy's journey to find his mother, embodying the "Cool Old Guy" archetype. His portrayal remains consistent as this benevolent grandfather figure.