Also, does Walk On require group name as well???
Yes, you do need a group name just to register.
You can just call it something as a place holder for now and I usually suggest the series you are doing or something easy to remember (such as "Sailor Moon" or "DBZ").
If you don't really want a group name, we can just list you as "Character X from Series Y" at the actual event. We usually don't have this on the groups list though because people like to keep what their costume is as a suprise until the event.
A small piece of advice for walk-ons is that we DO require that you have some sort of music to play while you walk on. Plan on going to the middle of the stage, doing a couple of poses, and then walking off. That's the basic requirement for a walkon.
I must say that I STRONGLY suggest that you don't just do a simple walk-on -- it's honestly terrifying!! It's actually easier to have something, anything, planned to get you to focus on that action instead of on the audience looking at you. Some people do a quick dance step, or a few in-character poses, or even just something cute like running on stage, waving your hand at people, doing a quick spin to show off your costume, and then bouncing offstage. The music really helps set the mood and also gives you something to think about, so pick something you like and are comfortable with so you feel confident, or something that suits your character (like the Sephiroth song for a Sephiroth from Advent Children). This really lets you get into character and makes things easier.
Best of luck! You'll do great!
Marisa