Even an A cup breasts weighs in the ballpark of 1 pound (~0.45 kg) on women with smaller underbust sizes. Either that's the densest bird in existence... or the scale is rigged against her.

Speaking of, I'm 90% certain those are meant to be a dove and falcon so I've added those tags. [edit: "those tags" not "that tag"]

This felt like a reference to a story of some kind, so I asked Gemini, and sure enough, it is.

"In a Buddhist apocryphal legend, a devout woman named Pranidhanavati encounters a starving mother bird (often depicted as a dove or a falcon) about to eat its own chicks. Moved by ultimate compassion, she cuts off her own breasts to feed them, placing her flesh on a scale against the bird. In a miraculous twist, no matter how much of her own flesh she cuts away, the scale will not balance, symbolizing that the weight of a single life is immeasurable and demands total selflessness. Moved by her pure sacrifice, the gods heal her wounds and transform her into a male prince, freeing her from earthly gender constraints so she can attain full enlightenment."