From Dragon Quest Wiki

Bladud (リバスト/Ribasuto in Japan, and Ruvas in the English NES release) is a minor character in Dragon Quest IV: Chapters of the Chosen.

The former owner of the Zenithian armour, he died defending the town of Bath from the monsters, and is now a ghost. According to the novel, which expands on his story, his full name is "Ribasuto Raru Kurutosu" and is considered a legendary hero with distant zenithian ancestry. He acquired all the Zenithian Equipment and stopped a monster revolt from destroying Casabranca. This explains the minor inconsistency of a seemingly normal person being able to use the heavenly equipment when Orifiela states that only those with Zenithian blood can use them.

He is aware that his armour was stolen, and upon it's retrieval from Briny Lair by The Hero, he allowed him/her to keep it. He will then depart to the afterlife, but if the party reenters the town after this scene Bladud will still be there, likely due to a programming flag.