This is the "Sponge Cleaner" from Sofina. It's in a 50ml fliptop bottle. The content is a clearish liquid gel, very faint scent that smells like generic face wash.
(It did come in a plastic sealed packaging but I threw that out ages ago)
This is meant to be a special cleaner for your sponges and powder puffs. I'm kind of a hygiene freak when it comes to sponges and powder puffs because ultimately, this is how all the makeup goes to your face.
For sponges I tend to use disposable ones (I buy those round sponges, cut them into 4-6 pieces, each day I use 1 new side and throw it out after day 2 (after both sides are used).
However for powder puffs that goes with pressed powders or powder foundations, they cannot be replaced as often (because sometimes they cost like $5 each especially the nice ones). This is where sponge cleaners become handy.
Here's my powder puff (Laneige one that comes with the Laneige foundations, it's interesting because it's a bit velvet like, and can actually apply a good fine layer of powder foundation). After 2 uses they tend to have either my powder resiue or a bit of foundation on it:
I don't really understand the Japanese instruction on the back of the bottle, but usually I squeeze a drop like this, and wet the sponge and just massage it until a bit of bubble comes out, and the sponge quickly will go clean:
After rinsing out all the residue or bubbles, my powder puff is good as new! (It's naturally a bit yellow tinted because other than the velvet top layer, the middle bit is a thin yellow sponge layer, which makes these puffs great).
Overall 5/5. You can buy various Shiseido or Sofina sponge cleaner for like $5 or 6 on Ebay generally for a 50ml bottle or so. Very cheap, and really keeps your things clean. They are meant to be anti-bacterial too.