Mamonde's Long-Lasting Liquid Eyeliner! I recommend this liquid eyeliner.

I had always used pencil-type products until now, but this is the product I switched to.
Perhaps because it is a liquid type, it definitely has the advantage of being good for filling in the upper waterline and not smudging easily.
The color is No. 2 Brown, and perhaps because it is a brown shade, it has a natural color payoff.
The color is distinct, but since it's brown, I'd say it looks natural haha.
I bought this product with my own money and have never once had any trouble with it smudging.
If you are looking for a smudge-proof eyeliner, I highly recommend this.
I remember the price was reasonable too, haha.