Love, you have been going out with this guy for 10 weeks.
God knows how soon you started having 'vanilla' sex with him, but he asked you FIRST time to piss in his mouth.
You said no.
He's not stopped asking.
That IS pressure. do you not see that?
You say he's great in every way, a bit emotionally distant, but so are you.
You can't and don't even have the intimacy to be able to discuss this matter properly. You are scared that IF you don't piss in to a grown man's mouth, an act you find EW, then you will lose him and so are considering doing it anyway.
IF A MAN WILL LEAVE YOU OVER THIS, THEN YOU NEED TO MOVE ON NOW!
For the love of god, can you not see that YOU DON'T KNOW THIS GUY! You've NOTHING invested in him, nor he you, this guy is a stranger. He is probably putting on an act to reel you in, but you won't know for sure for a long time to come.By which time it will be too late. He however is showing you just a little of the person he is, adn that little bit repulses you.
Think about it, if he is asking for THIS now, what will come later?
You need to listen to your instincts. They are SCREAMING at you. This guy is not right for you, he is a user, and more than a little warped. Forget that your friends know him, unless they shagged him, or lived with him, they won't know him enough to tell you anything about him. Also most people stay WELL out of advising others NOT to get involved.
Pack him in. Run like the frigging wind.