I'd recommend not deactivating your account (accounts don't get deleted, just deactivated) and simply not logging in again. That way if you decide to come back to Mibba sometime in the future, you can. You'll just simply log back in.
Since you're not allowed to have more than one account on Mibba, if you deactivate this one, that's it. You're not allowed to make a new one.
I'd recommend not deactivating your account (accounts don't get deleted, just deactivated) and simply not logging in again. That way if you decide to come back to Mibba sometime in the future, you can. You'll just simply log back in.
Since you're not allowed to have more than one account on Mibba, if you deactivate this one, that's it. You're not allowed to make a new one.