|Hair Color||Dark Purple|
San has long dark purple hair and gray eyes. San wears the school standard female uniform.
She seemed to be a girl with a boyish, serious and mature personality. She is good friends with Kazue Satou.
Nonetheless, San decided to go on the class trip, willing to risk her life to break the curse; she shared a room with Yumi Ogura at the inn. San was among the students who heard Takako's broadcast ("Makeup"), and left the room along with with Yumi. She was horrified when her roommate attacked Kouichi, but still caught her when he and Mei knocked her over while escaping. Unlike Yumi, San did not pursue the duo, instead attempting to escape the burning inn. In "Stand By Oneself," San, who had met up with Sayuri Kakinuma, Yukito Tsujii and Kenzou Kawahori previously, was making a run for the exit when a chandelier came loose and pinned her and the others to the floor. Kenzou, who was the least incapacitated, managed to free himself, but abandoned the others, only to be killed when a pillar collapsed on him just before he could escape.
While it is not explained how, it is assumed she was among the students saved from the burning inn by Tatsuji Chibiki, though San was knocked unconscious by the chandelier, as she was seen when the other survivors gathered outside the inn, she is shown inside Chibiki's car, being watched by the others, this is her last shown appearance as she is not shown with the group who visited Manabu Maejima in the hospital.
- Here name San (珊) means "coral".
- San surname Watanabe means "to cross the border," as well as being the fifth most common Japanese surname in and outside Japan.
- San is ranked B in "Another" characters ranking.
- Her home address is 3-14 Asamida Yomiyama City.
- She has only appeared in the Anime.
- San is the only survivor to be unconscious even when she is saved.