It's unlikely you see the catalyst of this event, or at least understand it. The entirety of Asgard can be, and frequently is tied to the Gods that protect it and what they have dominion over. The latent curses that Wanderers have sprung upon them are intangible proof, but when it comes to a God like Sigyn...her ties to the world are much more visible, apparent.

She's holed herself up in her district, tending to the earth with her hands and tools, like a human would. It distracts her, makes it easier to force her mind to feel things it isn't otherwise. Most Gods would know this comes with side effects; if snapped out of the state, she would as well. Right now, it's not so pressing a matter.

Her emotional unsteadiness doesn't come out as ugly or marred as one might imagine -- no, if you're standing outside when the magic takes effect, you'll be surprised to see large clumps of flowers curling up from the earth and blooming blossoms larger than they should be almost immediately after coming into complete existence. Some locations for these plants make no sense, taking root anywhere they please. Maybe in a patch of soil, or maybe on the side of a wall. Your roof, your bathtub, the very sleeve of your shirt.

Their sudden appearance may cause you alarm, enough to stay away on instinct. It's likely for naught, with just how plentiful they are. Smelling their aroma or coming into contact with their pollen is basically an inevitability. And when you do...something strange will happen.

• ASPHODEL → This flower will cause the feeling of soul-crushing regret and guilt. What's the one thing that you regret the most? The one thing you would change if you could turn back time? It's time to have that thrown back in your face for the next twelve hours, assuming you're not exposed to this pollen again. In the case that there is no big thing that you regret or feel guilty about, it'll be some small minor thing that has been exacerbated in your mind by the pollen to the point that it is now a big deal as well.
  
  
• CARNATION → After coming into contact with this flower, you feel a pull of absolutely clinginess that draws you towards someone you have some degree of fondness for, be it romantic or platonic in nature. There's this niggling feeling that won't stop pestering you, that you simply have to be in close proximity to this person. Hovering, observing, touching. Once you are? The feeling goes away. This magic tether lasts throughout the day, despite how your target may feel about it. If for some reason you can't be near this person, like they force you away by some magical means, your desperation strengthens as the proximity remains broken.
  
  
• EDELWEISS → This one will cause you to become extremely reckless. It goes beyond developing or exacerbating a hero complex. It's like experiencing l'appel du vide for twelve hours and actually listening to it. You won't be very susceptible to reason without some magic to put a stop to you, and your sense of consequence? Completely out the window.
  
  
• POPPY → Upon close contact with these flowers, you experience mild to severe synesthesia for anywhere from ten minutes to a couple of hours. Your senses mingle. You smell colours, see sounds. It often comes with a very mild sense of euphoria, but some find it disorienting instead.
  
  
• GENTANIA → When's the last time you had a good night's sleep? A few days? Weeks? Prior to ever showing up here? Here, let's help with that. The pollen from Gentania andrewsii, commonly known as a closed or bottle gentian, will instantly put anyone who comes in contact with it to sleep. It doesn't matter if they're sitting, standing, driving or swimming. They will fall into a deep sleep, varying anywhere from six to twelve hours. For the duration of that time, they will experience vivid nightmares, and will only awaken after experiencing sleep paralysis.
  
  
• IRIS → Apparently you're allergic to this flower. Don't worry, everyone else is too. Contact with this pollen causes a painful burning sensation. Don't scratch or rub at it, because that'll only cause it to spread. Washing the afflicted area or applying any sort of ointment or balm won't help. Tough it out. It'll only last a couple of hours.

The flowers definitely overstay their welcome, as does their magic. The blooms themselves will fall off and uproot themselves from their unnatural settings after about a week. The magic? It sticks with the plants for a whole day. The curse you're hit with might not last as long, but this means being careful: there's always the chance of being afflicted again. Maybe with two curses at once!

How will you know the curse is over? Maybe if you can put two and two together, you'll wake up in the morning and notice stepping outside doesn't...smell the way it usually does. The grass, any stray flowers, trees. None of them have any whiff of a scent.