You need a minimal amount because it burns intensely, although the applicator is such that it doesn't allow for a large quantity. The lips look bruised because it's black. The thing is, no matter how much it burns, I don't notice any plumping effect. The burning is pointless.

I am admittedly impressed by the three positive comments. I have used plumping products from other companies and they really do cause intense blood flow that gives the volume effect. This product burns my lips to an unbearable degree (without me having any known sensitivity) and does absolutely nothing – it works as a simple gloss which, of course, also dries out the lips since it is theoretically plumping. I tried to be patient, hoping at least the burning would subside, but unfortunately nothing changed and I removed it. Visually, it gives a nice look in terms of color because it somehow takes on the color of the lips, but the problem is the burning, which is unbearable