I called Mama. She was so happy she cried! She wants you to have her wedding gown. It's white lace.

Yeah, Osgood. I can't get married in your mother's dress. Ha ha. That-she and I, we are not built the same way.

We can have it altered.

Oh no you don't! Osgood, I'm gonna level with you. We can't get married at all.

Why not?

Well, in the first place, I'm not a natural blonde.

Doesn't matter.

I smoke! I smoke all the time!

I don't care.

Well, I have a terrible past. For three years now, I've been living with a saxophone player.

I forgive you.

[Tragically]

I can never have children!

We can adopt some.

But you don't understand, Osgood! [Whips off his wig, exasperated, and changes to a manly voice] Uhhh, I'm a man!

[Looks at him then turns back, unperturbed]

Well, nobody's perfect!
Note: the bolded line is ranked #48 in the American Film Institute's list of the top 100 movie quotations in American cinema.