The young woman on the train was so engrossed in her smartphone that her nipples were completely exposed—that was just way too unguarded.

The origin of the term Debagame lies in a real-life murder case.

The term Debakame is slang for a voyeur, but it originates from the name of the perpetrator of a crime that actually took place in Okubo Village, Tokyo, in 1908. It became a buzzword at the time—and subsequently entered the language—following a rape-murder case committed by Kametaro Ikeda, a habitual peeping tom who frequently spied on women’s baths.

Although Ikeda was sentenced to life imprisonment, he served only thirteen years; playwright Shin Hasegawa and others have pointed to the possibility that he was wrongfully convicted.