Hebi Shoujo

(This is the origin story of the Snake-Woman, and also the fourth installment of the Yamabiko Shimai series.)
Youko is a friend of Satsuki and Kanna. Her family is cursed since the time her grand-father injured a snake guardian spirit. After Youko's last relative is killed by a giant snake, a strange woman from a neighbor village adopts her, but somehow, Satsuki is worried about her friend.

Note: This version was published as a supplemental volume for Nakayoshi magazine.