I remember in October I was cosplaying Kyuubi from Naruto and got glomped by a bunch of people. I was sitting with my group as I got hot, and suddenly some guys decided to launch themselves at me. The muzzle and ears were bent out of shape, but I managed to get them straight again.
What was worse was that they simply walked away afterwards without even checking I was okay. It had been hard breathing in the costume beforehand, let alone with three guys bundling me. Luckily that's the worst I've had, most people actually did bother to ask permission before hugging me.
I myself hug people, but I always ask beforehand, and I know that no means no.
I've told all my friends this time only to let people who ask hug me, as I'll be in a Wolf Link quad suit (4 legs) so I can't really do much in terms of defending myself D:
Maybe I'll just bite them :3