Advanced Vissian starship encountered at a hypergiant star in Cogenitor, where Trip Tucker's friendship with a cogenitor ended in tragedy.
Vissian cruisers belonged to the Vissians, a friendly and technologically advanced species whom Enterprise met while studying a hypergiant star. The two crews mixed happily, and Archer spent three days inside the star's corona with the Vissian captain in a small probe vessel.
Aboard the Vissian ship Trip Tucker met a cogenitor, a member of a third Vissian sex treated as less than a citizen. He secretly taught it to read and encouraged it to seek asylum, and when Archer refused the request and returned it to the Vissians, the cogenitor took its own life.