Charybdis is a monster from Greek Mythology. She is Partnered with Scylla, who sits apon the cliff next to her.
No, Charybdis is not just a whirlpool. Unknown by many, there is actually a monster under the water. There is no description in any writing (that I have seen) of what she actually looks like.

--The whirlpool part of her, is when she opens her gaping mouth and sucks in. She swallows everything; water, passing ships, sea animals, everything.

--Then, she exhales and spits everything out. Everything flies everywhere.

Everything is timed surprisingly. These things happen at the same time every day.

Many heroes of Greek Legend traveled by here safely; and many died. But who hears the story of the hero who got eaten by Charybdis? No one.

If you would like to know a little more about Charybdis, then check out the actual writing of the poet, Homer. Click here to see Book 12 of the Odyssey!