I drank my friend's boogers
Eww. I really hope you are joking. Why did you do that?
I did it because I was bored.
There are much better ways to entertain yourself when you are bored. It is not sanitary to drink the boogers of anyone.
It was his own boogers, he didn't mind.
You do not understand how gross this is and I can't imagine how sick it made you. You need to stop this immediately.