One of my most used designs is this sturdy telescopic back scratcher. Nice sharp pointed edges on the head combined with a robust print in place telescopic handle. Print both pieces and just twist the head in to the handle. Little bit of resistance when threading them together, but it should work out great.

No supports and I kept it at 100% infill to avoid weakness to be sure you'll never have to print another from breaking, but feel free to adjust it lower if you arent as worried about the strength.

UPDATE 1/1/2025

Because of requests I've made the points on the head all the same length instead of staggered. I've also added a small outer brim to the handle since some were having issues with it coming loose. If you still have trouble since I didnt add the brim to the inner layers, just change the brim for the handle to Outer and Inner. You'll have to trim it all off to get it to slide properly. However 90% of fails is because you need to clean your bed