She was one of the women Dr. Tenma dated (or at least tried to). Dr. Becker described her as "a woman with beauty and talent," and said that those two things equal a night of love. Dr. Tenma laughed and said he had to meet her first. He was walking to the restaurant where they were supposed to meet, but saw a store selling a cuckoo clock like the one Adolf Junkers wanted as a kid. He stopped by the store to purchase the clock, thus making him late for the date.

When he arrived at the restaurant, the lady wasn't there anymore, and Dr. Becker said it was because he was late. It was actually because Eva followed Tenma to the restaurant and provoked her until she was gone.

(Monster Wiki)