With the way you've drawn it, I'd say it's less graphic and more "visual". It gives me a mural vibe because of how you've made the lungs and ribs blue like flowers, as opposed to making them dripping red with blood and innards. I think because of that, you can get away with not giving it a mature tag.
It's definitely disturbing, but the color choice and positions kinda make it disturbing and beautiful, so to speak. I work with a cartoonish style myself, but I also have posted body horror outside of the mature tag: