Ask HN: Should we give a discount to a billion dollar startup?

We are a 5 months old SaaS startup with a fairly high monthly pricing ($1000+/month) with 7 paying customers. A large startup signed up recently for a month and now wants to prepay for a year but is expecting a discount on the list price (~50% discount). We have offered them a discount of 2 months, which I know is not substantial but given that we are bootstrapped till now, we are really in a dilemma. Any advice from people who have been in a similar situation would be helpful. Thank you.