Pakuyasa is the former student of Sakata Gintoki whom he designated to the supplies because he is not capable of combat.
He might be a projection of Sakata Gintoki that Pluto Batou saw during their battle prior to the series.
Pakuyasa greatly resembles Sakata Gintoki especially the hair and clothes during the Jouishishi war where he has a white headband and a white yukata . He has a permed silvery-blue hair, an angry pair of eyebrows and a double chin. He looks like a fatter version of Sakata Gintoki.