Manual payment method (backend only)

Manual.php

<?php
class Akjumii_Payment_Model_Method_Manual extends Mage_Payment_Model_Method_Abstract
{
    protected $_code = 'manual_payment';

    protected $_isGateway = false;

    protected $_canAuthorize = false;

    protected $_canVoid = false;

    protected $_canUseInternal = true;

    protected $_canUseCheckout = false;

    protected $_canUseForMultishipping = false;

    protected $_canSaveCc = false;

    public function isAvailable($quote = null)
    {
        return Mage::app()->getStore()->isAdmin();
    }
}