Brynja Heringsdötir is Sissi's pen-pal from Iceland. She was only seen in the Episode Kadic Bombshell. She is voiced by Jodi Forrest with a thick Norse accent. She is very kind and good at speaking English/French. When she arrives, all the boys in school go nuts over her (even Herb rejected Sissi for Brynja) and all the girls wanted to know her beauty secrets. This makes Sissi jealous. At first, Odd could care less about her, but after getting a good look at her, he becomes obsessed with her. She also seemingly takes a liking to him as well, calling him the Icelandic word for "sweetheart". Odd and she began dating in the one day they knew each other. That afternoon, Odd introduced Brynja to the group. Like every other boy in the school, Ulrich and Jeremie fall in love with her.
She is voiced by Jodie "Jody" Forrest.