John Mayer teases Jessica Simpson

These days Jessica Simpson is rarely seen without boyfriend John Mayer. The pair have been spotted all across the country together and recently got back from a romantic trip to Rome. But it's not all bliss for Jessica and John. He has been known to slight the perky popstar for her notorious airhead persona.

According to Australian tabloid NW, John's latest insult towards Jessica came during a trip to Il Piccolino Trattoria, a Los Angeles restaurant, with several of their friends. At one point in the evening, Mayer presented Simpson with a gift, which she was expecting to be romantic. Instead, she found herself holding a thesaurus. A snitch told NW, "[John] said she should know more words. The whole table erupted in laughter."

John's cruel joke left Jessica feeling unappreciated and her friends and family very angry. They were already worried about the couple's future after rumors recently started swirling that John had had a fling with Alicia Keys in New York.

But despite of her loved ones' worries, Simpson appears to be getting closer to Mayer. And Mayer is said to be serious about her. He has even been telling his pals that Simpson "is the one he wants to settle down and start a family with," according to NW. No wonder the couple were looking at diamond rings while in Rome.