estrus:

A period of sexual heat during which animals copulate . Sex at any other time is highly unusual.
Etymology: From the Latin oestrus, meaning frenzy, or to rush violently about.

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eye-fuck
F factor, the
F**K
F**K word, the
F-A-B
F-all / f-all
F-him / F-her
F-ing
F-ing around
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F-plan
F-U2
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F-you!
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face fucking
faceless fuck