Participates in the assembly of the infectious particles by decorating the outer surface of the capsid shell and thus forming a layer between the capsid and the tegument. Complexes composed of the capsid protein VP5 and UL48A assemble together in the host cytoplasm and are translocated to the nucleus, where they accumulate and participate in capsid assembly. Participates in the assembly of the infectious particles by decorating the outer surface of the capsid shell and thus forming a layer between the capsid and the tegument. Complexes composed of the major capsid protein and small capsomere-interacting protein/SCP assemble together in the host cytoplasm and are translocated to the nucleus, where they accumulate and participate in capsid assembly. Interacts with the major capsid protein/MCP. Belongs to the herpesviridae small capsomere-interacting protein family.