The animation seems to be censoring Fengxian's actual physical condition, probably bcs they consider it would be too graphic. It's explained in the LN since she's suffering from late-stage of syphilis her nose is already decaying or in the terms usually used in describing syphilis symptoms, her nose already 'fell off'. The manga also depicts her with decaying nose and rashes all over her body But I would also like to interpret this as how we see Fengxian from Lakan's pov, an eternal beautiful flower even if it's already whithering
