Assimilate and Masturbate

[Note: there is a lineart-only version and shading version of this available on my Pixiv page here: https://www.pixiv.net/member_illust.php?mode=medium&illust_id=64629247 ]

Shape-shifting is that kind of ability that grants anyone, especially preds, an incredible, invaluable advantage. Slimes make the most out of this ability to get one over on their prey <3

Assuming the shape of an otherwise harmless person or creature is a common tactic. This disguise tricks prey into dismissing the pred as something they can safely ignore. Taking an attractive or otherwise sexy form, which the given prey would otherwise find appealing, is also a sure-fire way to not only deceive the soon-to-be meal, but to willingly make them come to the pred's greedy embrace.

Then finally, assuming the exact same shape of the prey? Well, that's just downright playful :3

This last tactic will of course not work on every prey. It may help the pred to devour their friends, but unless the prey loves the idea of being eaten by themselves, this won't be ideal~
Lucky for this slime, Hex Maniac is just such a hopelessly lewd and perverted individual, on which this approach might actually the be best one <3

Our friendly, hungry slime is actually Ditto! Possibly the sneakiest of all Pokémon. It's taken the shape of Hex herself, and even to its surprise, she's REALLY loving it.

Ditto in this case, is not actually eating and digesting poor Hex, even if she'd totally be into that happening. Instead, Ditto's encasing her completely, from toe to head~
Once consumed, Hex will be coated in a perfect copy of herself, which will completely control all of her actions. Ditto will essentially live her life for her. All she'll get to do it experience her life through the actions that Ditto takes for her.

Perhaps ditto will use this new, assumed identity to eat some of Hex Maniac's friends? It'd be the easiest thing in the world, now that they'd think Ditto's the real Hex. If Ditto isn't hungry at the time, it could force them inside Hex's real body. Whether they end up getting digested or not is her problem e//3//e So many possibilities...!

So watch out the next time you come across Hex! She may not be who you think she is >;3 Then again, unless Ditto hides that careless little smile of his, atop Hex's head, it may be easier to spot than anticipated...