Snake-like creatures with a bright blue octopus head. They used to be humans, until they were kidnapped by the Channelers and subjected to Seath's experiments.
At least two of the Pisaca were Princess Gwynevere's handmaidens. These two can be found in the lowest part of the the tower area in the Duke's Archives, but unlike the rest, they do not attack even when provoked, but will instead keep crying. This is supported by the Miracles they drop, which are only usable by members of the Princess Guard Covenant:
Soothing Sunlight & Bountyful Sunlight
Special miracle granted to the maidens of Gwynevere, Princess of the Sun.
The miracles of Gwynevere, the princess cherished by all, grant their blessing to a great many warriors.