Seth Rogen is Engaged

NEW YORK (CBS) Seth Rogen is officially off the market.

The actor is engaged to girlfriend Lauren Miller, he confirmed on the first episode of "Conan" Monday night.

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Rogen and Miller, a writer, have been dating since 2004. But, he told host Conan O'Brien, he had a hard time containing himself when he bought the engagement ring.

"Literally, I felt like someone had given me like a truckload of heroin to hold onto," Rogen said. "I felt like the feds were going to kick in my door at any second. I couldn't have a conversation with my girlfriend. All I could think of was this ring. Like 'Don't say "Lord of the Rings!" Don't mention anything about a ring!'"

And when it came time to propose, he continued, Rogen admitted he may have chosen an inopportune moment.

"She was in our closet changing, and she was literally only in her underpants, and her boobs were out," he said. "I'd already kind of started, and I was like 'Oh man, her boobs are out! That's not part of the plan!' I didn't picture it like this, and I know she didn't picture it like this. No little girl is like 'It'll happen in a closet with my t--s out.'"

Rogen and O'Brien also talked about California's Proposition 19 and Rogen getting in shape for his upcoming film "The Green Hornet." Watch the interview: