Thanks to this Thread i realised that i played a lot of games and dont have a main game.
Got 450 hours on csgo but i have not played that shit since 2016 or so. Maybe League of Legends since 2013 every year some weeks but i dont know how much hours in total.
For mainstream games, it's absolutely Skyrim. I suspect it's EASILY 1k+ total hours played. No other game comes close.
For adult games, it's likely Free Cities. I was a fiend back in the day. I don't have any exact amounts, but it's likely 100+ hours. I've also spent considerable time playing EratohoK and Lab Rats 2, and while LR2 may pass FC someday, I doubt it has yet.
From the porn games I think that would be "Such a Sharp Pain", followed by "Away from Home" and "Guilty Pleasure".
As for non porn games (Steam or non-Steam) - "World of Tanks Blitz" 915 hours, "ETS2" - 800-ish hours, the regular "World of Tanks" - at least 7500 hours (30,000 battles, maximum time 15 minutes (or less, if my team is people with brains), that makes at least 7500 hours, probably a lot more.
I have Fallout New Vegas as my absolute champion. I can't say how many hours I spent on it, but I went through it 5 times (2 times in the vanilla version and 3 times with mods).
Sadly it has to be League of Legends for me. Even with slowing down recently.
For porn it has to be Once in a life time. the story was accually enjoyable to follow on. Also helps that I didn't know games had a skip option when i was playing it.