Where does it go hard

I JUST EXPLODED INTO RAINBOWS AND LOLLIPOPS!

I meant to make a lame joke.
You, seeing the rappers, makes you hard, referring to the fact that a penis becomes erect, or "hard" when a man is sexually aroused. If you were to become "hard" when seeing the rappers, that would make it seem as if you were homosexual. Homosexuality is commonly looked down upon in American society, especially in the younger years of people's lives.