Kim Jong-nam, the eldest son of former North Korean leader Kim Jong-il, communicates by e-mail with a mystery contact in South Korea, according to a new book by a Japanese journalist. "I asked an acquaintance in [South] Korea to send [a cartoon depicting new North Korean leader Kim Jong-un] and already read it," Kim Jong-nam writes in the collection of over 100 e-mails exchanged over seven years with Yoji Komi. Kim sent his messages to Komi using a Korean Yahoo e-mail account. "I don't think there are any problems with me using a Yahoo Korea account," Kim said. "Anyone used to be able to sign up" without the peculiar requirement of many South Korean websites to submit a resident registration number. Kim and Komi met in Macau in January 2011. Kim at the time told him, "I have a couple of close Japanese and [South] Korean friends" and was close to Japanese, Americans and South Koreans at boarding school in Switzerland. "I was able to get back in touch with a lot of friends through Twitter and Facebook. I have reunions with them several times a year in Europe and Southeast Asia."