Yassan (やっさん Yassan), also known as the Literary Girl, is a second-year student at Sanada West High. She is well-known for having a crush on Hidenori, and their riverbank encounters are a running gag in the series.
Yassan has a slim figure and is of average height. She has black eyes and long dark-violet hair that reaches her waist. She is usually seen wearing the West High uniform, with tall dark socks and sometimes the lavender school sweater.
Yassan is a romantic with rather fantastical ideals, having gone to a riverbank to try and experience a boy-meets-girl scenario that she had written down in her novel. Upon succeeding in a sense, she tries her hardest to preserve the scenario, even becoming aggressive towards those who threaten to break it down. Her subsequent infatuation with Hidenori leads her to somewhat extreme forms of behaviour. She chases him on sight (much to his annoyance) and is also a bit paranoid, such as when he sees her walking with another guy who was just a classmate.
Yassan gets embarrassed easily and frequently. When Hidenori glared at her for laughing at him, she took it to heart and was ready to apologize, appearing extremely guilty. She was also almost in tears after knocking him out inadvertently.
Additionally, she is one of the less vocal characters in the series, having only a few lines and communicating a lot through facial expressions.
Yassan is fairly athletic when she wants to be, being able to match Hidenori (who is himself athletic) for pace and outlast him over distance.
Her epithet stems from her hobby of writing novels.
- All her acquaintances call her 'Yassan', which is likely a nickname and not her real name. A certain 'Yasunaga-chan' mentioned in HSGF-16 could refer to her.
- Yassan’s hair, while dark violet in the anime, is portrayed to be black in the manga’s color spread.
- Yassan placed 10th in the character popularity poll, securing 3,855 votes.