Fierce warrior people of Elas, whose women's tears can make a man fall helplessly in love.
The Elasians are a proud and arrogant humanoid people from the planet Elas, locked in a long conflict with neighbouring Troyius. To end the war, the Federation arranged for the Enterprise to carry Elaan, the Dohlman of Elas, to marry the ruler of Troyius, though she showed little interest in the match.
Elasian biology includes a powerful chemical in women's tears that leaves any man who touches them infatuated, which is how Elaan came to bind Kirk to her. Kirk had to overcome its effect while a Klingon ship and a saboteur threatened the mission.