Persona 3 , played time is at about 120 hours , BUT , i think i feel asleep once or twice while playing it sp , lets remove 30 houra from that and saw an even 90 hours . I believe sandbox games dont count hence why i didnt say oblivion. Although i got to nyx at about 100 hours , spent 20 hours grinding to be able to kill him.
EDIT : i see people talking about years so ill add that too. Legend of dragoon , took about 10 years and 4 playthroughs . Ever play through i did i stoped at the end due to boredom ( at the law city ) . About 2 months ago i decided to replay start to finish , none stop , fell asleep a few times ( yeah a bad habit i know im only 22 btw ) so i clocked over 100 hours due to me being asleep and the game still running . But i finally saw the ending ... Disapointing to say the least.