Image imported from derpibooru
Original Description:

Days before graduation, Ruby had a breakthrough with her potion making. After hundreds of tweaks, she had finally perfected her breast growth potion to the point where it was safe and stable, causing enormous growth for two hours, ending in a massive release of milk when they shrunk back down. Ruby was over the moon that she had finally completed it, and decided that the best way to demonstrate her success would be on a grand scale. It was quite the sight to watch the dragon walk across the graduation stage with breasts that had to be carted in wheelbarrows, leading to many gasps and pictures taken… along with laughs from Midnight and Nina.