What's the best solvent for eyeliner? I'll tell you what it is. It's tears. The harder you cry, the more it hurts and the longer you cry, the more effective it is. I didn't have any eyeliner left by the end of tonight. Saved me the trouble of having to get it off. Oh, one less thing to do in the day. Side effects: red eyes, red nose and a sore feeling inside me. very sore.