A pair of D-cup breasts can weigh between 15 and 23 pounds, "the equivalent of carrying around a six-month old baby boy."
This is not accurate for a lot of reasons.
1: we don't know her band size
2: as depicted here she's certainly WAY more than a DD.
3: the way bra sizing works is really hard to get a reasonably accurate assumption just on the bra size alone. You'd really just need to weigh them.
Source gf is an HH cup and her life is fucking hard lol.
Quote is from- https://start.askwonder.com/insights/breast-weight-cup-size-chnzscjew#:~:text=This%20source%20also%20states%20that,breasts%20likely%20weigh%202%2C800g.
Edit got the gfs cup size wrong
How heavy are double-D boobs? I think they could carry enough momentum to knock out a lucky person.
A pair of D-cup breasts can weigh between 15 and 23 pounds, "the equivalent of carrying around a six-month old baby boy." This is not accurate for a lot of reasons. 1: we don't know her band size 2: as depicted here she's certainly WAY more than a DD. 3: the way bra sizing works is really hard to get a reasonably accurate assumption just on the bra size alone. You'd really just need to weigh them. Source gf is an HH cup and her life is fucking hard lol. Quote is from- https://start.askwonder.com/insights/breast-weight-cup-size-chnzscjew#:~:text=This%20source%20also%20states%20that,breasts%20likely%20weigh%202%2C800g. Edit got the gfs cup size wrong
Soft and Protective 
Indeed 😏
https://www.pixiv.net/en/artworks/82695968
Helltaker is a lucky man
Helltaker: Takin da chains and da booba LIKE A BOSS!!
Great for winter