I don't plan to continue this series as it's clearly not for me, but for those who keep saying it makes sense for her to be an S-rank adventurer because her son is the hero, setting aside that it's very natural for Hero's to come from anywhere even two people who can't fight at all (otherwise there would be Heroes all over the place), that doesn't quite line up. First off, she's a healer, not a warrior, not a mage knight, a healer, so if his class was something she passed down to him from her? It'd be something magic based like a sage, not something that's more physically based like a Hero. Second, just because the mother exercises well doesn't mean her son is born with a lot of muscle, her individual rank doesn't translate much to him unless she trained him but as established in the last chapter the son basically treated her like dirt, and MC who knew this family since childhood didn't know she was so talented. If you're still enjoying it fine, if you prefer to just take what the story gives you and roll with it sure, but if you're going to argue when people express skepticism (mostly due to how she was a worthless slave despite being a former S-rank Healer, making her basically the most valuable slave that slaver has ever had even if the world considers her ugly) that's a really poor argument.