This is my number one eyeliner and believe me I've tried A LOT of eyeliners.
L'Oreal Superliner Black Lacquer - Approx £7 (depending where you buy it from.)
I know that a lot of people love this eyeliner and a lot of people really don't like it, but it's one of the only eyeliners I've tried that actually stays all day on me. It's really easy to apply, I love the nib, just makes applying eyeliner a quick and easy job instead of a chore!
I would even say it's waterproof, my eyes are forever watering and I mean constantly, which is really annoying but once this eyeliner is completely dry, my watery eyes don't affect it! Which for me, is amazing!
You can easily do a super thin line, or a thicker line, I sometimes use it on my bottom lash line as well and then I smudge it out with some dark brown or black eye shadow to create a smokier look.
I really honestly can't get enough of this eye liner, it's a little bit more pricey than a lot of eye liners but still very affordable and I will definitely be re-purchasing. I have heard a rumor that's it's going to be discontinued and in that case I am going to massively stock but while I try to find an effective dupe!
It's so easy to use so I would recommend it to most people, it does have a glossy finish which sometimes I like and sometimes I don't which in that case I just put black eye shadow over the top to block out the shineyness.
The packaging is nice, very sleek and classic, easy to hold while applying and not slippery.
If you ever see me wearing eyeliner 90% of the time it's this one, absolutely love it!