"I was wondering if I could stay with you," you say, blushing. Bessie laughs.
"You can if you want to," she says. "Of course, I only have one bed... but it's big enough for the two of us!" You blush even more. You decide that you might as well share the same bed with Bessie.
"I'm tired," Bessie says, yawning. "In the morning, we can go to town or something. I'm going to bed; if you can't sleep, feel free to drink some of my milk. Don't worry, it doesn't seem to affect you. Goodnight!" With one final yawn, Bessie shuts her eyes and quickly falls asleep. You lay in bed, just a few inches from Bessie. You must admit, she is pretty attractive... You blush again at the thought.
After staying awake for a while you discover you can't get to sleep. You glance at Bessie's udder. After a brief internal struggle, you put your mouth over one of her teats and suck. You hear Bessie moan. She must be able to feel this even when she's unconscious. After a minute or two of drinking you begin to doze off.