Yumi's weight is 45kg, to lift her in the air you would need to bloat her belly to 45m3, or to 4.4m in diameter, which is a bit too much I think :)
how big can her belly inflate to at max?.
Not sure, but much less than 4.4m in diameter... I think once I got her to bloat to ~20L
ok.
it doesn’t have to be realistic because it’s a game.
