You can’t delete your account. Use the tip below to obfuscate your personal data.
There used to be a way to remove all your lists in one go, but due to perfomance reasons this option is removed. So you have to do it by hand.
More info can be found here: http://myanimelist.net/forum/?topicid=298846#msg10792692
URLS:
http://myanimelist.net
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