Kaeloo/Fridge

Fridge Horror

In Let's Play Baby-Sitting, Kaeloo agrees to seduce Mr. Cat in order to produce a baby for Stumpy to take care of. Now consider the anatomical differences between cats and frogs. Thankfully, it never got to that stage thanks to an emotional outburst on Kaeloo's side before anything could happen. However, if they'd gone through with the plan, it would not have ended well.
So far, we've only seen four inhabitants of Smileyland and have been given insight into the past of three of them, the other being the "guardian" of the place. What happened to everyone else?
The scene at the end of Let's Play House just seems like a naughty little joke, but the implications of the entire scene, from Mr. Cat rubbing his groin against Kaeloo's to the honking sound effect that played once the lights went out were rather unfortunate. In other words an attempt at rape had just been shown on-screen. Granted, the fact that she can transform into a hulking monster and beat the stuffing out of him lessens the impact, but it is more the idea that Mr. Cat might not be above raping his friend which is truly frightening.
Yoghurts are shown to be sentient in Smileyland. Quack-Quack eats them by the crate.
The Carnivore Confusion Mr. Cat must have as a result of constantly being around a duck, a squirrel and a frog.
Kaeloo's psychological profile in general. At times, to prevent herself from transforming into Bad Kaeloo out of rage, she forces herself into a wired-open grin. She also puts a lot of emphasis on being 'cute', 'sweet' and 'nice'. The fact that she was so overjoyed to die via being crushed by a meteorite in Let's Play the Quest for the Wholly Gruel indicates she may even be suicidal. Add to that her readiness to leave Smileyland in Let's Play Courtroom Drama when she decided her other personality was a serious threat to her friends and it quickly becomes clear that Bad Kaeloo is holding her hostage in her own body.

Fridge Brilliance

Kaeloo denies being a boy or a girl, but is clearly female. Then you remember that for some species of frog, gender isn't exactly a fixed attribute, and that hermaphrodites aren't a rare occurrence among amphibians.

Fridge Logic

Why is it that Kaeloo claimed that she needed to get angry to transform in Let's Play Scaredy-Cat, yet in other episodes she can hulk out on demand?
We've seen Mr. Cat shapeshift, why doesn't he just turn into something that can kick Bad Kaeloo's ass?

The transformations are involuntary. Bad Kaeloo beats him up so much it changes his form.

How the heck did everyone get to Smileyland? Smileyland is a planet, and the cast seem to be from Earth.