A curious cultural fact, but it's true: Japan is a country of stalkers.
The phenomenon is a by-product of other cultural traits. Firstly, the hidden, repressed nature of sex in Japan; sexual relationships, while fairly common, are never publicly acknowledged. This means that commonplace 'Western' forms of courtship and gender interaction, such as flirting, are pretty rare and many men never develop mature ways of dealing with their sexuality. Secondly, Japanese men are emasculated and socially repressed from an early age; without effective social networks and with poor social skills, it is easy to fall into anti-social behaviour such as stalking or internet addiction. Thirdly, women, traditionally passive, are often unwilling to 'cause trouble' and complain about stalking to police or authority figures. Finally, the stalking behavior, incredibly, is not always seen as negative; it can be perceived as part of the tradition of 'gaman', or endurance, where ineffective and futile repetive action can be seen in a positve light: the stalker often believes he is courting; and indeed some Japanese dating guides suggest behaviour such as following your 'target' around waiting for the chance to create an 'accidental' meeting, over a period of weeks.
So stalking is pretty common; in fact, it is very rare to meet a Japanese woman who has not had at least one stalker, and many have one or more at any given time.
Western women living in Japan are not immune. Far from it; many Japanese men who become stalkers are obsessed with the curves, personality and hair and skin colour of Western women. You'll pick one up pretty quickly if you live here, and even quicker if you are young and live in the countryside.
Japanese police are infamous for doing nothing when stalking is reported; they are so well-known for their lack of sympathy that women very rarely try going to them; which results in massive under-reporting of stalking cases.
The most famous recent stalking case involved Tatsuya Ichihashi, who stalked English teacher Lindsay Hawker. After stalking and then killing her, Ichihashi was on the run for two years, changing his name, working, and having plastic surgery to alter his appearance. He was finally caught last month.
Most stalking cases don't end in murder but they are always unpleasant. A couple of first-hand accounts, all from my days on JET.
A British woman notices several underwear items go missing over a period of weeks. Somewhat alarmed, she tells her supervisor at the Board of Education, who tells her to hang up her smalls...inside. Which she does, only for more to go missing. Now she goes to the police, who merely tell her to hang up her undies inside (which she was already doing) and lock the door (which she was doing).
Months pass, things regularly go missing. There seems nothing she can do, life goes on. Finally a culprit comes to light...one of her 13-year-old students from the fist year of junior high school! Apparently this lad had been crawling through a ventilation window at ground level (too small for an adult) and nicking her underwear. It was only his mother that found them when searching his room...some 40 different items! Well. The police pass her on the BOE and eventually, after several days, a man knocks on her door, introduces himself as the lad's father, and gives her about $400 worth of Japanese yen 'to pay for more underwear', and also offers all her old stuff back...strangely enough she doesn't want it back, and she spend the rest of the year teaching the boy as usual in her usual school class.
Another teacher comes home to find her window open, her bed messed up and semen stains on her sheets. The police merely tell her 'lock your doors and windows' and when she asked about DNA testing, said 'we don't do that here'. Similar occurrences meet with the same response. She knows, from being followed, who the guy is, and after telling the police, she is told 'it is not him'.
And one Japanese woman I knew, a student when I was teaching, showed me pictures on her mobile phone her stalker had sent: pictures of self harm, bleeding razor cuts on arms and legs, supposedly to demonstrate his love for her. The woman told me she admired his 'gaman spirit' and the last I heard was that they were getting married!
But hey, who am I to criticise another culture that I obviously don't understand...