For reference, my waist measures 96 cm and my thigh circumference is 45 cm.
I chose size L after contacting customer service for advice, as I previously had sizing issues with another pair. They recommended this size, even though according to the size guide I would normally be between S and close to M.
In the end, the fit is good. It could maybe be slightly more form-fitting, but I personally find it comfortable as it is.
I would recommend going at least one size up compared to the size guide if you want to be on the safe side.
Also, customer service was very helpful, responsive, and attentive—thank you for the support!