Task: Question Answering
Input (English): Passage: In the summer of 1990 in Los Angeles Leah has just been named as the West Coast editor for a magazine owned by Nelson Publishing. Her new job will begin as soon as she returns with her two best friends Nikki, and Bonnie from her annual vacation. Nikki is a divorced woman who refuses to trust any man due to her ex-husband's cheating, and Bonnie is a married mother who loves her husband but hates the routine her life has settled into.  As Leah is recently separated from Mac Chambers, and it is her turn to plan the vacation, she chooses Rome. Leah had previously spent two months there during the summer of 1970 and had been romantically involved with a young Italian artist named Marcello. After learning of the trip, Mac, hoping for a reconciliation with Leah, encourages her to go see Marcello and wants time with her when she returns.
Upon arriving in Rome, the three women find that their hotel room shares a bathroom with another American. Joe is a recently retired New York City police detective who was recently left at the altar and is taking alone his intended honeymoon, as the trip had been prepaid. Nikki is struggling with the sharing of the bathroom. The women then go sightseeing, ending up at Bernini's Fountain of the Four Rivers in the Piazza Navona. Nikki comments that "it doesn't look the same as in the movie" (A nod to the 1954 film). The ladies agree to throw their coins and make their wishes at this fountain since they do not want to walk all the way to the Trevi Fountain. 
Question: Whose hotel room shares a bathroom with a retired detective?
Output (English): Nikki.