Last issue, Viper, the female head of Hydra, put Jessica Drew’s roommate Lindsay in the hospital and possibly crippled her for life.
This issue, Spider-Woman hunts Viper down, seeking vengeance. When she finally catches up to her, Spider-Woman learns that Viper is possessed by the demon Ch’Thon, who also is tied to Spider-Woman’s origin, and…Viper is Jessica’s mommy!
Later, in Captain America #281, this gets undone and explained as a deeper magical manipulation by Morgana LeFay, which causes Viper to suffer from constant delusions.