From the looks of the old leaves I think you had a Haworthia. I would take it out of the water and cut around the red line.

The flesh should be healthy with no brown spots. If there are brown spots inside the cut keep cutting till it’s clean and free of rot. Let the cut callus over for a couple days somewhere shady and dry. Once a scab has formed repot in a mix of half cactus soil and half perlite or pumice. The pot should have a drainage hole. Keep in bright filtered light and no water till roots form. Roots can take up to a month+ to grow so just leave your guy be, and let him do what he needs to do;).

Could you take a pic of your plant as is please:). I’m curious of how it looks.

Is the 2nd photo showing the plant before it was knocked over? If you do not mind me saying, it looks really bad. It looks like it was watered too much. It is, or was, a haworthia, but difficult to say exactly which one. Possibly Haworthia attenuata or similar. They look something like this:

IMO, succulents should not be in glass of water. But some can take it, and even root. White fuzzy stuff could be harmless, but could also signal beggining of rot. Succulents are arid plants that store water in their leaves and lots of water often kills them.

Your plant seems to be growing roots. If it was mine, I would take it out of water, use paper towel to soak up all extra water. Tip of the main root looks black (besides fuzzy white stuff) and likely soft, I would cut it off. Here is pic - cut where the yellow line is:

I would let it callus, out of water or any mix. How long, it depends on how wet it is. Maybe a day or could be few. After, it should be stuck into fast draining mix, and it may grow. I can't see if there is any of the plant left?

I see Kara posted as I was typing...yes, keep cutting if there is any black in the flesh or the root. Post clear photo if not sure.

Rina luckily you said something because I totally forgot to add the photo with the red line;). Lately I haven’t had issues with posting pics.

I didn't send this one initially, because it didn't show the roots, but here it is. I think that Kara was correct. It looks just like a Haworthia.

What is the 2nd photo in your initial post of?

Rina I believe they’re a bunch of dead leaves. That’s how I was able to guess it was a Haworthia. From the looks of it the Haw was rotting.

Maybe the cat knocking it over was a blessing in disguise.

Yeah, that's the pot that it came out of... It had been knocked down and played with by cats, when we rescued what was left of it, that is what we initially put into the glass of water...

Craig you should have no issue rooting yours. I just declumped an old neglected clump of Haworthia attenuata. I cut a bunch heads off about six weeks ago and they were all rootless. I cut right were I put the red line in my first comment.

All of them are well ancho and have roots.

Yours have roots so cut around we’re Rina put her yellow line or right under the roots.

Pot it up with half cactus mix and half perlite or pumice in a couple days. After the cut has scabbed over. From your second pic your Haworthia looks like the pot may have been too big. Overpotting isn’t the best thing for succulents. Your little guy should go in a small pot that has drainage holes. I would personally wait a couple days to water.

Yes, I could see hat they are Haworthia leaves, just was wondering what they were - part of plant or all. I can tell they are rotted too. Definitely good for plant it got knocked over, otherwise it would all rotted...

I have rooted many that didn't have any roots - never in water. Here are just few - that was year ago, they are much bigger now:

It is a Haworthia, I'd take it out of the water before it rots. I'd leave it out of water for a day to dry.
Then I'd pot it up in C&S mix w/ Perlite (50/50 blend) & do not water it for several days at least since it has no roots.