Alright, so I'm 22 and have been RP'd for a couple months now.

So I had been hanging with a girl off and on for about a year now, she wants to go trip acid and wants me to tag along and drive her and her friends around. Normally, I wouldn't see a problem and would join in on the fun but, she hangs with one of my good friend' sister who is also going. My friend (lifelong, his mother is my GodMother so I grew up with them for the most part) doesn't want his sister to go do acid and shit so I told the her:

"No go, I'm not gonna go drive his sister around when he doesn't want her to be doing this shit". I don't want to feel guilty for going behind his back and enabling his sister (who's like, 18) to go trip.

What do you guys think, good call or am I just being a prude?