Referral/Corporate Code
It is not uncommon for this field to be left blank, but there are two possible entries:
1)  Referral Code - If you're being referred to Romancing the Mouse from a past guest, enter the email address of the past guest and you are eligible for a 30% Referral discount.  You also give that past guest a 5% additional discount for their next visit.
2)  Corporate Code - If your company has a arranged for a corporate discount, enter the corporate code to prove eligibility for your company discount.  If you're eligible for this discount it is usually the reason you found Romancing the Mouse.