(from ebookjapan):
Kayo and her friend Miki are happy to welcome their father, a researcher of tropical plants, back from abroad. When the father opens the bag containing the South American plants he collected in the greenhouse, he is bitten by a rare poisonous spider that was mixed in there, and suffers from a high fever with a bruise from the poisonous spider on his cheek. After that, the father begins to act strangely, and the mother is also attacked by something and gets a poisonous spider bruise on her cheek. Then, a terrible evil hand sneaks up on Kayo, and ......!