You shouldn't reinforce the leather on a bag like this even if the reinforcement is very flexible, otherwise it's gonna dig into you everytime you move or stick out and dig into everything else surrounding youSure! Many luxury fashion houses reinforce their bags with a flexible material prior to crafting the bag. This bag, unfortunately, doesn’t seem to have much, if any at all, which makes it look very slouchy very quickly. (Maybe at the bottom of the bag) Remember, messengers are wide bags and have a tendency to slouch regardless. If the bag isn’t reinforced, it will happen almost immediately upon use as the leather softens, some leathers will slouch much faster than others, ie calf, Togo, etc. I was triggered and repulsed by some pictures of used/preloved Kelly messengers that were on the resale market and their condition, especially considering the bag was just released last year!!
Besides this level of slouchiness is part of the look wether you like it or not