Glims are the little orbs you'll see dropping around the battlefield, either from getting a "Nice!" during combat, or from Mr. Drippy as a bit of a pick-me-up. Introduced by Mr. Drippy, they are color coded to help you understand what they're useful for. Green glims will recover your Health Points, while blue glims will restore your magic points. Golden glims will unlock the special ability of whichever character you're controlling. The ones to watch out for are the Purple Glims, introduced when you encounter:
These purple glims will actually damage you, and I am not certain whether or not they'll count for this trophy. Simply progress through the game and you will come across near enough, especially if you level up your familiars and complete as many errands/bounties as possible.