G.S.I. Gross Sexual Imposition
G. S. I. is like being touched in a sexual way but not getting the full experience. You can still get in trouble even if you had sex before.
He touched me, but I said 'you didn't even leave a mess!'
My friend had sex with him before, but this time he just grabbed her leg. She said it was G. S. I.
I got in trouble because he tried to touch me, even though we had sex before.