This lip liner blows my mind! It's truly smudge-proof, which is very rare - it doesn't bleed when you eat or drink. The colour stays put for hours, as it is water-resistant.
Another nifty invention: the pencil is self-sharpening. The tip is sharpened every time you twist off the cap, allowing for precise application. It took me a while to figure this out though...
The colour is high-impact enough to wear the liner on its own under lip balm, but this would look great under most dark shades and would give them a rich, bluish undertone. Definitely a worthwhile purchase!