Irrevocable love.

It's the burning sensation everytime they reach for your hand, a fire is lit the minute their skin graze your wrist and interlocks your fingers. It's hard to breath when their around like smoke has filled the air making your breaths heavy and smoggy. That's the first sign.
Looking at them is the hardest thing you've ever had to endure, they are so bright, they are the sun that lights up your whole world. Without them, everything in your world would shrivel up and die, including you. But the only thing harder than looking at them would be looking away. That's the second sign.
Their voice the most beautiful thing you've ever heard, like a thousand harps all playing the same beautiful song. In a room full of a million people, their voice is the only thing you can hear. That's the third sign.
Their eyes are like sirens luring you into their depths forever to drown and sink further and further into them. That's the fourth sign.
You know them. You've always known them. Even before you actually knew them you'd known them. You'd travel through lifetimes, search through a billion stars to find them. And you'd never not ever leave them. That is the fifth and final sign.
All of these signs together mean that you are truly utterly completely irrevocably in love.