FWIW I had a similar behavior on my (work) MacBook pro for a while. I'd unplug it from my screen for the weekend and find it overheated with a dead battery.

Turns out I kept bumping the Bluetooth mouse which kept waking it up, and it would stay awake for a while, even with the screen closed. Disabling the permission for Bluetooth devices to wake it fixed it, but I had a couple of Mondays where I couldn't do anything for a half hour while the machine charged up enough to boot.