This is mainly for book readers but
I don't know if you guys can see his pin close enough, but it's a Mermaid, which is the sigil of House Manderly....so clearly this is Wendel Manderly, at the Red Wedding.
YOU GUYS KNOW WHAT THIS ****ING MEANS RIGHT????
I TOTALLY THOUGHT THAT WAS GOING TO BE LEFT OUT I AM SO EXCITED!!! House Manderly is definitely my second favourite Northern house