The story's main is Kuronuma Sawako who is nicknamed as the ghost in the movie 'The Ring' -- 'Sadako' because of her scary looks and behaviour. But actually, she is a very shy and gentle girl who wishes for friends to spend time with. She always admired one boy in her class who is surrounded by a lot of people and always smiles gently. Little by little, she's doing her best to make friends and be liked by other people.
Both shows feature students going through their highschool every day lives and overcome issues related to that. The focus of the two series is a bit different, with kimi ni todoke being on the romance side, but both have a lighthearted humour with a somewhat similar school theme.