If you're uncomfortable, say no. If he can't respect you or your faith to accept that and back down until marriage, then he isn't worth your time. He's just a desperate dude trying to guilt you into giving him some free milk. Tell him to piss off.
shadha-
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You may shoot me with your words,
You may cut me with your eyes,
You may kill me with your hatefulness,
But still, like air, I'll rise.
BREAST CANCER