wewe can't I'm afraid. You'll just have to make do with making your page blank, saying you're no longer a memeber and never coming back. But if you're really determined to be deleted wewe can ask for people to ripoti wewe because if enough do I think wewe should be deleted.
wewe shouldn't really care as you'd be dead but wewe could get someone to change your kauli mbiu to the fact you're deceased au something. Hope it's alrigt if i answered that.