Who is Udzir from Extras and what is their importance?

Udzir is the leader of the Extras. On several occasions, he tries to explain to Aya and Tally and their friends about his people's intentions, but Tally never lets him finish. When Aya finally learns the truth, that Udzir and his people want to establish a space colony, she convinces Tally of this truth. Udzir later becomes the face of the Extras to recruit new colonists.