"I would like. We don't have a good idea what mana actually is, all we know is that Witches power our magic with something our bodies generate slowly. We can feel how much we have, sorta. Using too much at once knocks us flat for a few minutes, and using too much in one day makes us unable to do further magic, but doesn't necessarily impair us physically. We generate less mana as we get older, which is no longer a problem for me at least."