noob attempt at a write-up:
(lore warning)

>beyond rare cases of suffocation, slime girls are generally harmless to creatures
>except to other slime girls, because they can easily absorb mass from each other (especially if their target is smaller)
>there are systems in place against unlawful theft of slime, including a method to drain illegally large slimes of their mass and give it back to the victims
>this mechanic upholds a balance in the slime hierarchy and has allowed them to peacefully coexist with other species for centuries
>at this point size theft has dropped to near zero levels, because the punishment for this severe crime is that they take back what you stole plus a little extra, leaving you smaller forever
>
>be human
>discover potion that lets you morph into a slime temporarily
>go to decently populated area a good distance from the capital
>ambush other slime girls and steal their mass
>many of them dont even fight back because its basically a free lawsuit for them with no lasting consequences and no real harm
>they think they will get their mass back (and be paid damages) as soon as youre apprehended and put on the drainer
>watch their indifferent, mildly inconvenienced, or smug behavior as they shrink into a tiny version of themselves and you grow even bigger
>theyre clueless and think youre the clueless one
>move on, keep gathering more mass
>get labeled essentially a mass criminal without killing anyone
>soon enough youre gigantic
>law enforcement comes slow as they havent seen a theft this large in decades, and most local slime police offices scrapped their drainers in budget cuts. they dont have the means to arrest you on the spot
>back ups are called in with lots of drainers on the way from the capital
>potion wears off
>start turning into a human again
>the arriving back up forces shit bricks as they watch the transformation unfold
>realize they can no longer take your size back
>their slime drainers are powerless
>youre not made of slime