Lasher

The Avatar meets Lasher the Unicorn in Dungeon Destard in Ultima VII.

Lasher is a typical Unicorn, and also has quite a dose of sarcasm when the Avatar asks obvious questions. Lasher tells the whole story of the Unicorns, but only if the Avatar is still a virgin. If the Avatar has had sex (namely in the House of Baths), Lasher is so disgusted he avoids the Avatar like the plague. That's because as all unicorns, he is a virgin detector.

Trivia

 * It really works! Screwing around will disgust Lasher.