I.e., games that hooked you in and you couldn’t stop playing until it was finished. Not games that just happened to be unexpectedly short. And by “completed” I guess I mean the main story etc, not 100%ing the game :).
For me, it would be Catherine, Bioshock Infinite and Black Mesa (although I think I got to the final area then had to go to sleep and complete it the next day). I also played an ungodly amount of Hades in one sitting, but didn’t get the “full” ending in one day.
I first played Infinite in college and the game took me about 15 hours to complete on PC. That game is a work of frickin art. One of the prettiest ever made.
I actually only just played BioShock 1 & 2 for the first time recently because the whole series was on sale in the Nintendo store for dirt cheap. So I ended up playing the whole series on our Switch while my wife watched. She’s more of a watcher than a player. I’ve been loving her watching me play the new Zelda. It’s cute.