|Anime||Episode 9 (Flashback)|
In Episode 9, Matsunaga explains on the tape he left in the old classroom what had happen during the class trip in 1983. After praying at the shrine, Class 3's teacher, Mr. Koga, declared everything would be okay and the class is free of the curse and they left.
When Hamaguchi was struck by lightning, the class began to panic, and was scrambling to get down the mountain before something happened to them. As the class struggled to get to a safer spot, the unfortunate Yuki slipped and fell off of the mountain's cliff. In her fall she banged her head and then her back against many trees on the way down before finally falling of a rocky side of the mountain, causing her to break her neck which undoubtedly killed her - if she wasn't already dead from internal injuries coming from hitting her head and back.
- Her surname means "star river" or "river of stars".