We get used to our own penis that is why we do not feel big even when we are.
If your erected length are over 5 Inch length or you are approaching 6 you are big enough to make a woman squirt and feel wonderful squirting orgasms.
As you say, most men in those movies have their penis appear bigger then it is. This will warp your sens of reality, and you will start to believe that every man walking around in reality, are walking around with a 10 Inch long penis. They can make a 7 Inch long penis appear as if it was 10 Inch and a 5.5 Inch penis appear as if that was 7 in those movies. They can even edit videos in post production and use CGI (Computer-generated imagery) to increase the size of the penises (I don't know it they are doing that?).
These videos can destroy your brain.
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