Romance
Elle and Lui's romance is one that appears to have burned hot and bright. Ironically, for all the passion with which their relationship burns is the same thing with which fuels their romance ending in such turmoil and pain. It is their unbridled passions that they turn to in the midst of this rather than any reason, and reason eventually catches up to them.
Memorial
A memorial was built in honor of those killed in the bombing of Hiroshima. It serves as a reminder of the great horror that was perpetrated upon the innocent people of the city. It is a monument to death which keeps the horror of the war at the forefront as ironically many people too quickly forget the tragedy that occurred there years prior.
Lui
Lui has fallen for Elle, and found himself in a romance with her. Ironically he has a wife at home who he is betraying by sleeping with Elle to fulfill some need within him that he only allows to last for a short time.
Hiroshima
Elle compares her relationship to Lui as similar to the bombing of Hiroshima. Ironically, Lui's family was killed during the bombing that she is describing as being like Hiroshima.
Bedroom Suite
Elle goes to the apartment where here and Lui made love. Ironically, she has a difficult time entering it again as it has now become a place of great remorse as their relationship is ending.