Delek is a member of the Tok’ra High Council, and thus one of the leaders of the Tok’ra.
He has had limited dealings with Earth, and not very successful ones.
The interests of the Tok’ra are of highest importance to him, and he is worried about the Tok’ra alliance with the Tau’ri and the Jaffa, since he fears it may get too many Tok’ra killed. He fears for the survival of his people.
Delek appears to have a somewhat lower view of human hosts, or at least fears too strong hosts will affect the Tok’ra in an unfortunate way at this point in time. He does not wish the Tok’ra to receive more hosts from the Tau’ri.
We do not know the name of Delek’s host.
We have seen Delek in the episode: “Death Knell”. Delek is played by Sebastian Spence.