One recent survey showed 42 percent of single men and 44 percent of single women between ages 18 to 34 were virgins, with some men calling women "scary". Another found nearly 25 percent of Japanese men and 14 percent women aged 50 were yet to marry - the highest figures since census began in 1920.

Surprisingly, even some married couples have lost the spark in the bedroom.

A Japanese family planning association's survey found almost half of the married couples had not had sex for more than a month and did not expect that to change in the near future-"sexless" marriage, as the association defines it. While 35.2 percent of married men said they were "too tired" to have sex, 22 percent of married women said they found sex "troublesome".