Antina was a character who was introduced after Scott Adams received too many complaints about Tina's stereotypical nature. She was an engineer, and appeared in two strips, January first and second, 1996. When she encountered Dilbert, his tie flattened, possibly meaning he was aroused (Scott Adams made the tie flat only once before, too show that Dilbert had "lost his innocence" with Liz).
According to Seven Years of Highly Defective People, after Scott Adams introduced Antina, he received complaints that he was mocking lesbians. He admitted that he had only created Antina to stir up trouble and got rid of her after she fulfilled her role as a one joke character.