Karambit
This is a repost of someone else's work. It is no longer on Thingiverse so I thought I would upload it. I am not sure who first created it. I modified the grips to make them a little wider so the screws fit better. I also made a display stand that would hold this.
1) Glue both blade haves together with some Gorilla Clear Grip https://www.amazon.com/Gorilla-Clear-Contact-Adhesive-Waterproof/dp/B06WGSRM4Z?th=1 or any other adhesive you may like.
2) Then screw the grips and blade together with some M3-.5 X 12 screws. https://www.lowes.com/pd/Hillman-3mm-0-5-x-12mm-Phillips-Drive-Machine-Screws-12-Count/999994898
3) Enjoy!
I printed the blades in white so they could get painted. Or you could print in the color you want. (I had white around.) I printed the grips in white for one and black for another. Again use any color you want, this is just what I had around.