I just googled Charybdis being a bit confused as I recalled it only as a sea monster.
The sentiment behind the tattoo is a positive take on nihilism. Just because the world has no inherent meaning or value doesen't mean you can't live by your own. "A king and a peasant both rot the same beneath the sun, and no living can tell their bones apart". It is sort of a personal reminder that the battle against time is futile. Therefore, it is important, since life is finite, to place value and meaning where you think it matters most to you. Because ultimately we all drown in the maelstrom of time as the wheels of infinity turn. Don't waste your time trying to become rich or famous for the sake of it, don't treat happiness as a destination but appreciate the present and realize that happiness is found in the journey.
If you live life only looking forward to the pay-offs you are wasting your time away. You got one life, and you got it for free. So when you die you actually lose nothing. Take risks. Stop to place your feet in the running river to feel alive and take in the nature around you. The other people jogging in these woods never stop to take in what they already have, their eyes are locked on what's always over the horizon out of reach.
We all perish in the maelstrom of life. Fight the current and it destroys you. Rush with the current and it destroys you. Let it carry you but gaze upon the sun as you relax and enjoy the ride and it had meaning.