Charybdis

"Charybdis’ whirlpool had to be at least seventy feet in diameter. Just looking at her made me want to burst into tears. She could make even a grown man cry for his mother."

- -Chase Grace

Biography and Appearance
Charbydis is a large female sea monster that appeared in Homer's ''Odyssey. ''She drinks from the sea throughout the day forming a large whirlpool. Three times a day she spits back out whatever she consumed as a method of filtration. The whirlpool itself is about seventy feet in diameter, enough to consume an entire ship. Beneath the water, Charybdis appears a hideous black mass that anchors to the bottom of the sea floor, large crusty teeth extend from the whirlpool's perimeter.

In The Grace Curse
Charybdis, alongside her partner Scylla, are summoned by Apollo to kill Chase in the San Francisco Bay. Charybdis attempts to drown Chase in her whirlpool to which she nearly succeeded in before Chase electrocuted her. After being injured, the mass unanchors itself and disappears into the distance.

Trivia

 * According to Chase, Charybdis itself is a metaphor for the thing's in life that drags you down slowly, but becomes inescapable.