Sai

Sai
Sai, as he appears in Rei Gaiden.
Name in Kanji	サイ
Name in Romaji	Sai
Family	Mari (little sister)
Position(s)	Orphan boy
Appearances	Rei Gaiden

Boogaloo (ブーガル, Būgaru)

Appearing in the first Rei Gaiden one-shot, Sai is a young boy whose parents were killed by bandits, who also kidnapped his little sister, Mari. He meets Rei on his journey for revenge but collapses due to exhaustion. Sympathizing with the boy, Rei takes revenge for him and reunites him with his sister.