Aisle (as in the period aisle) (used to be Luna Pads but they've rebranded to be more inclusive) might be similar to what you're looking for? they offer a range of sizes and styles of period underwear & period boxers, as well as reusable pads, liners, and cups. the underwear and boxers have a built in absorptive layer and can be worn on their own during periods, ya just bleed on them, or you can use them in combo with the liners and pads (pads probably undies only i think? unsure. boxers sit 1/3
differently against body between the legs compared to underwear, which might be why it’s hard to find pads that work with boxers?). the liners are designed to fit into the boxers/underwear, and i believe when you purchase either options it includes a liner (called a booster) but you can also buy additional liners. 2/3
i have not tried the underwear or boxers myself, but i use their old style pads (from before the rebrand). the company is fairly detailed in describing different materials used for absorbency, is fairly chemical-free, and is transparent about where they are manufactured. they have also partnered with a number of projects in the past to bring clean menstrual products to people. 3/3
aisle
For anyone else who might be interested. The boxer briefs are out of stock, but they have other products.
