All pictures taken in natural light without flash.
This is a felt-tip liquid eye pen, very much along the lines of Clio Waterproof Pen Liner. The difference here is the pen tip: Clio is chubbier at the base, then taper to a point, whereas VS is quite skinny throughout with a longer pen tip. You can get a fine line with both, but it's probably easier with the VS pen since a slight tilt of the hand with Clio will produce a thicker line. I usually make a dotted line, then go over in one stroke to connect the dots.
The formula for all both pens is slightly different also. Clio is thin and runny, whereas VS is quite thick, like a creamy ink almost. As you can see from the swatch, it does not run or bleed much at all, even on the back of my hand which is usually dry and prone to feathering. So formula wise, VS wins! Clio still leads for the staying and lasting power though ^.^ VS lasts longer with primer, and without primer it smudges a bit on my oily lids, which I honestly expect given the thick and creamy formula. I still like this pen a lot, so if you see it on sale, try one!
- Blackest Black: an intense opaque jet black without shimmers, identical to Clio.