Flowers and Flames
This idea was born from my craziness but encouraged by my friend (elliot . the . wizard) who you should totally go and check out :)
Shadowhunters are all different kinds of flowers.
Downworlders are different types of flames according to species and the colour of their flame matching the colour of their soulmate's tattoo.
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In The Clave's idea of an idyllic world, flowers would be paired with other flowers and flames would be paired with other flames but, naturally, this is not the case.
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The flower is initially a small tattoo on their arm, near the elbow, closed and dormant.
When they meet their soulmate, the flower unfurls and blooms.
When they talk to their soulmate, their flower grows.
The more time they spend with their soulmate, the larger it becomes, until it reaches the maximum size.
After that, new flowers grow and spread until they have a garden of tattoos.
The garden isn't always visible – they can choose if they want everyone to see it or if they'd like to hide it – but their soulmate can always see it.
If the soulmate dies, the garden shrivels and dies.
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The flame is initially a small tattoo on their arm, near the wrist, usually still and unmoving.
When they meet their soulmate, the flame starts to continuously flicker.
When they talk to their soulmate, the flame grows.
The more time they spend with their soulmate, the larger it becomes, until it reaches the maximum size.
After that, it sparks and spreads, ending up as a full-fledges fire.
The fire isn't always visible – they can choose if they want everyone to see it or if they'd like to hide it – but their soulmate can always see it.
If the soulmate dies, the flames are doused.
So, this is my AU! If you have any ideas or suggestions, please let me know!