Season 7, Episode 14 - "Old Boyfriends"
Rose finally remembers who Thor Anderson is, and it's not a good memory. She used Thor to make Charlie jealous by going to the Valentine's dance with him her senior year. As Thor is leaving, he kisses her goodbye, and she instantly remembers details of their first kiss. Why does she remember?
Thor didn't know how to kiss in high school, and nothing's changed 40 years later.
Rose: It was the haystack!
Thor: What?
Rose: Our first kiss! It was at night, and the air was crisp. You were wearing a blue and white striped shirt. And we were in a haystack!
Thor: Yes! Yes, that's it! But you said you couldn't remember.
Rose: Well, I guess I just needed a little help.
Thor: Ah, thank you, Rose. Thank you. You don't know what that means to me.
Blanche: Rose, you remembered! A kiss unlocked your memory.
Rose: One doesn't forget a kiss like that.
Blanche: Oh, that's so romantic!
Rose: No, it isn't. That man didn't know how to kiss 40 years ago, and he doesn't know how to kiss today.
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