Unless you are born rich, charismatic, good-looking or masculine, you would probably be able to get a beautiful girl on the left. But mostly, this isn't the case with people like us. And as such, 2D anime would be the only option for a girlfriend that could accompany you at home. Much of these examples could well be seen in love simulation games in the market. So what exactly are the differences between 2D and 3D girls?
1.) Proportions - You could probably get the right 3 sizes of your favorite girl with little flaws...
2.) Personality - From Tsundere to Yandere, Cute to Bossy types, you could get your favorite in these games...
3.) Money & Dating - Ya don't need to spend a single cent on dates and stuff. (Except the price of your game and electricity bills)
4.) Feelings - Somehow or rather, 2D doesn't betray you. (Unless you got a bad ending) Nevertheless, they won't cheat you of your feelings.
However so, there are certainly some things you couldn't do without a 3D girlfriend as feelings in real time are different in comparison with something out of your monitor screen. But points 1 - 4 will probably be something to toggle with...
