Poor Fluorine! Forever one electron short of that sweet, sweet noble gas configuration! With only 9 electrons, it's just dying to snatch a 10th and complete its outer shell. It's basically the elemental equivalent of someone staring longingly at the last cookie in the jar that they can't have.
Fluorine is so electron-hungry it's practically the vampire of the periodic table - the most electronegative element, ready to sink its teeth into any electron-rich victim that passes by. No wonder it's so reactive it can burn through glass and make water burst into flames!
Next time you brush your teeth, remember your toothpaste contains a compound with this desperate little element that would literally explode with joy if it could just get that 10th electron!