I'm back. XD
After I do the "claim" with the old might-be-the-right shared secret I got, I received this message from claim@emailname.moc
"Hello,"
"Unfortunately the secret you sent does not match the shared secret of the board /grotoner/. However, since no one has logged into the board since its creation, it is up for claim and I can therefore reassign it to you again."
"After your first login you can also change the password to something of your choosing."
"Username: Grotoner_One"
"Password: jiOLtQYAblsu"
"Shared secret: 我爱中国"
"Thank you for using 8kun, anon!"
Well, my English skill gets improve by reading, good news:-).