Jewel Anemone
Anemones are considered the flowers of the ocean, named after their beautiful namesakes on land. There are over 1000 varieties and they come in all shapes and colours.
But don't think you can win some brownie points by giving a bunch of them to your loved one. Underwater anemones are animals not plants. They're like a cross between coral and jellyfish and have stinging tenticles loaded with nerotoxin harpoons.
If you want to 'say it with flowers,' unless you have something nasty to say, it's always safest to stick with roses.