Vaire is one of Shu Aiba's servants following his transformation into the Necrodiver. Alongside Varda and Valar, Vaire manifests physically to aid Shu in combat against the Hadeans. Within this trio, Vaire embodies the offensive role, contrasting with Varda's logical analysis and Valar's defensive capabilities.

Despite the servants' initial portrayal as primarily logical entities, Vaire demonstrates a capacity for compassion. Vaire points out alternative approaches Shu could take during conflicts that would show greater consideration for others. Over time, Vaire and the other servants gradually develop more human-like traits and emotional understanding. This evolution stems directly from Shu's consistent dedication to protecting his companions, whom he regards as friends.

Vaire participates in battles using the Necrodiver's specialized abilities, including attacks like the Yig Sword arm blade and the Tailbone spine whip. Vaire supports Shu as he confronts both the Hadean threat and transformed former allies.