Fandoms of any size are encouraged, any female character you've seen hate against (even if it's just from a few people) is eligible. You can write meta or fic, make graphics, share fanmixes, or basically anything else that's celebrating the female character you've claimed. There is a limit of three claims per language per character (so, three people could create for a character in English, and three more in Spanish, and three more in Russian, etc.). There are a lot of women characters out there who get hated for some pretty misogynistic reasons. Let's spread some love!
I will be doing Honor Harrington, because she was my favorite fictional character when I was a teen and very important to me, and I just recently (not for the first time) heard her dismissed as a caricature and a man with boobs.