Everyone is born with two different types of flowers on a persons hand.
One flower would represent yourself, the other representing your soulmate.
The stems would be intertwined with each other and the vines would crawl up your hand and wrap around your wrist like a bracelet.
They would continue crawling down your arm and around your body, advancing farther and farther on the day of your birthday, until you meet your soulmate face to face.
If, and when you do, the vines would start to retract back to the bracelet the same way they did crawling up your body.
The more time you spend with your soulmate, the faster the vines retract.
You could write on your hand and the message would be put on your soulmates hand so they can read it.
If you're soulmate was feeling sad or depressed, the vines would tighten around your body.
If this happens, you would put your hand on the flowers, and your soulmate would feel the sensation, realizing that you would always be there for them.
If you're soulmate dies, their flower would wilt and die, the same stem would grow your new  soulmate flower in the span of a few days.

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Bakugou Katsuki had been wondering his whole life who his soulmate was.
When he was younger, he looked up the meaning for marigolds and carnations, and being surprised at what he found.
Marigolds fit his personality perfectly, but the carnations, were the complete opposite.
They meant pride and beauty, but this one was red, and they symbolize pride, love, and admiration.
Katsuki was dumbfounded, who ever his soulmate was, they had to be a complete and utter idiot.
Little did Katsuki know, his soulmate was closer then they appeared.