Just because you can divide yourself, doesn't mean you should.
There are limits to these things, you know? But the ringing slime doesn't think that far ahead. It can't, really. It's always sliding itself around, unable to sit still. Even while
"resting", its body shakes and wobbles, little micro-twitches, accompanied by a small, constant thrumming. One being is simply not meant to contain so much life. And so, when the feeling is too much to bear, it splits itself, rising into a tall pillar and then sinking with such force that it tears in two, resulting in a satisfied sigh from the newly created slimelets.
Of course, that energy returns soon enough. It's inevitable, a product of the ringing slime's natural ability to absorb anything from sunlight, to beast sheddings, to the leftover scraps and bones that adventurers carelessly abandon during their delves. With a metabolism like that, it can hardly be blamed, right? Soon enough, these smaller slimes will begin to shake again, twitching in unison, the humming rising in pitch, harmonizing, until the process repeats, and now you've got four of the things.
Occasionally, a ringing slime will stumble into a lucky meal, like the full carcass of some defeated beast or human. When it absorbs with so many surplus calories all at once, well... it's terrifying. A growing waterfall of new slimes, rising and splitting, rising and splitting, until the room is buzzing loudly with the happy relief of countless twitching miniscule goo. The tiled dungeon floor will start to waver in front of your eyes, a natural mirage. Your senses will start to leave you, and you worry that the wave of wobbling green will suck you in and eat you, too.
So you need to cool it in front of the humans, okay? We're trying to keep the peace, here. When you suddenly split from one slime to a thousand in the course of a minute or less, surrounding them like an expanding bog... well, you can't really expect them to do anything but run away screaming.

