It’s been a while since I’ve traveled by Amtrak so i can’t say I remember how small those bathrooms are, but standing sixty-nine would certainly work. Just put a shower cap on her head so she doesn’t brush the floor with it accidentally. The throne (reverse cowgirl with you seated instead of lying down) also comes to mind.
Don't drink, don't smoke? What do you do?
Go to Sheri's and party like a madman, what else?