Add a "Subject" with Meeting Scheduler

I love the Meeting Scheduler but can you please add a field with “Subject” or “Topic” or “Related to” or something so I know what the heck the candidate is interested in talking about. I send out mass mailings and emails with my “Book a Time with Me” and many time I have no idea which position a candidate is booking for or whether it is a new prospective client. It would be so helpful!!!