These events are awesome! I have been and it feels like being at a mini-con but without the crazy ticket prices. They take professional photos, offer snacks/drinks, have raffles & events, and even teach some ballroom dancing.
Cosplay is not required but you are free to go all out. Just note you want to be comfortable to dance and move. Avoid bringing big props and don't dress overly casual (jeans, filp-flops, t-shirts etc.) as it is a ball. there is even a cosplay contest! It's super fun to learn some ballroom dancing to the tunes of various anime and gaming music.
I don't mind purchasing tickets for you directly. It's $10 up until the end of 9/20/19. You can purchase tickets quickly on Eventbrite for $12.24 or it will be $15 at the door.
There is very detailed information & ticket options here: https://www.facebook.com/events/2152074284921707/
6:00 pm - 7:00 pm: Welcome hour for socializing, photography, and open office hours for dance instruction.
7:00 pm - 8:00 pm: Beginner dance lesson taught by one of the Bay Area's top dance professionals, Daniel Lee Tran.
8:00 pm - 9:00 pm: The party begins! Social dancing with occasional icebreaker activities.
9:00 pm - 9:15 pm: Dance demonstrations by some of the Bay Area's top performers plus prize-giveaways
9:15 pm - 10:00 pm: More Dancing!
10:00 pm - 10:15 pm: Cosplay Contests as well as additional performances and giveaways
10:15 pm - 11:00 pm: MORE Dancing!
11:00 pm - 11:15 pm: Final announcements, giveaways, and performances
11:15 pm - 1:00 am: Party the night away!