Jenna is ready to have sex with Jake. And she just happens to tell the whole school that in this scene.
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Matty offers Jenna advice on handling her first time with Jake on Awkward. "What Comes First: Sex or Love?" is the sixth episode of the second season.
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Awkward Season 2 Episode 6 Quotes

Lacey: I am sorry we got carried away with all of that girl talk. I did not mean to embarrass you.
Jenna: Don't worry it wasn't the first time.
Lacey: And it won't be the last.

Jenna, contrary to the advice I've been giving Ally; you need to know that every first time is the first time, and it should be special.

Lacey