The fabric has a 3-layer structure with a waterproof membrane in-between two layers of fabric. When leaks occur, they're contained within (between the inner fabric layer and the waterproof membrane), keeping your clothes and/or sheets clean.
The absorbent layers go up the back of the panties, making them comfortable and effective for period underwear. They absorb a good deal of blood.
The waterproof membrane means great daytime protection whether you're standing or sitting, and good nighttime protection whether you're a stomach or back sleeper.
It feels like your wearing a regular panty. But it does it job, no unexpected leaks through clothing, leaves her worry free to get through a period day.
Cleaning is super easy, machine wash/hand wash and air dry.