Guy likes girl, girl likes guy.
Guy smokes pot
Girl does not.
Girl is strong enough to voice her opinion.
Guy goes cold.
He’s at least decent enough to NOT get involved, and you’re better off having gotten away without starting a relationship – only to find out after things got serious.
One thing to remember is that if you get involved now, he will say to you three years from now, ‘You knew what you were getting into.’ You don’t want that thrown back in your face.