Veyko was a female Vissian.
She was part of a delegation of Vissian's who came aboard the Enterprise as a part of a cultural exchange. She was the tactical officer on the Vissian ship. She met Malcolm Reed while dining in the Enteprise mess hall with Commander Tucker. Reed hit it off with her, since both were tactical officers. He gave her a tour of the ship. Veylo and Reed became romantically attracted to each other, but the relationship ended when the Vissian left the ship due to Tucker's meddling with a Cogenitor, a third party used by the Vissians for breeding purposes. (ENT: "Cogenitor")