According to the artist, whatever was used as the basis got 335 likes so they grew by ~34cm. The image tweet is at 26k likes so if she got hit by it again they'd grow by 26 meters, but I'm pretty sure feesu isn't into hyper stuff.
Hey...It's easier said than done if my breasts were to get bigger so easily!BANZAI, OPPAI-SAMA!!An advent!With everyone's power, have bigger breasts!What is this!? Change me back!!Huh!? HUH!!?What do you want?Kasumi-mama? Do you have a minute?