Share a fic that you have reread multiple times, and why you'd recommend it

It can be either ongoing, or completed.

I'll start: Zenith of Stars AO3, FFN by Yuesya/XxZuiliu.

This is a Jujutsu Kaisen fic, and the protagonist has the Mystic Eyes of Death Perception from the Nasuverse. I enjoyed it because it was incredibly well written, and has a good balance between character dynamics, action, and clan politics. Highly recommended.