Serious wasn't a problem, anyone who didn't take it serious would soon enough, and it wasn't like you could force someone into believing how horrific things were. Emma had gone from normal to fairytales, to dragons to other realms and then here. She was already in the realm of 'it can't get worse'. However Stiles got to that point was up to Marrowood really.
"Okay, you can take a breath." The kid wasn't lying when he said this might take a while. "So far, we know that there are two wolves, a few vampires, some witches and... magic users," she wasn't calling herself a witch, that wasn't what she was. It wasn't spells and potions and whatever like the other witches, they had wands. "There's a bit of a mixing pot going on." That wasn't including the people that fought zombies, came from the future and the assassin superhero gang.
She knew about magical barriers though, she practically was one herself. "But I can promise we're trying to find ways to stop bad shit happening to people. We're definitely not going to let anyone get possessed again, because I really don't like the Further."