The Merzy The First Pen Eyeliner is a brush pen eyeliner that is easy to use.

This is the eyeliner I’ve settled on. I use it frequently because it allows me to draw a simple line quickly. The line is so sharp that I don't need to apply any other touches. It washes off cleanly, so I don't have to worry about impurities. Since it is a soft brush pen, it would be good for beginners as well. You just need to be careful when closing the cap, though, as it can split.