21 and 17 is legal is most states. I dont see a problem with it. There is usually a 5 year rule so 23 and 17 would not be legal. I am 28 and my wife is 24. If we were younger when we met we would fit the same profile but we were adults when we met. On the other hand 50 year old men are dating 20 year old girls now that is wrong and women are doing the same thing. Who knows maybe I wont think that it is bad at all when I get to that age, lol.