 In the medieval Japan , <unk> gentleman were not very interested in a woman 's physical beauty and rarely had an opportunity to see it . The only physical attribute of interest was a woman 's hair , which had to be thick and longer than she was tall . The fascination with long hair was one reason why a woman 's becoming a nun was regarded with such seriousness — it could never again grow to its full length . This explains why Genji refuses to let Murasaki ( his de facto wife in the classical Japanese novel The Tale of Genji ) take the tonsure when she is ill . 
