You ever buy yourself flowers, leave them a bit too long and then the bouquet starts to rot? This smells like that day before the rotting begins. And I said buy YOURSELF flowers, but yes, you can also be given said flowers and have the same experience *eyeroll*.
Before a flower bouquet begins to rot, something happens within the cells and they can no longer absorb water due to stem blockages (this is why you must trim them regularly to have a lasting bouquet). In this scent, you can detect that damp accumulation. It's full of water, too-late trimmed violets, and sharp stems.
Upon first spray you're hit with a combination of lilacs and wet cobblestone. in the dry down, you're out for a brisk walk in the fall evening, shuddering under the spitting rain. You didn't want to go for said walk but you've had a long, melancholic day and you'v been told going for a walk is good for your mental health. You keep looking over your shoulder since the evenings have quickly become darker. The sidewalk is slippery with wet leaves and fungi. You cut the walk short as you feel a pair of eyes burning into the back of your head. You take the back way to your house and the dirty corners of the unmaintained alley hit your nose for a second until you cross the threshold of your home and the bouquet of forgotten flowers quickly reminds you that they're due for a trim.