Reference for Ketubot 81:2

<big><strong>גמ׳</strong></big> וליתני אנסתי לא מבעיא קאמר לא מבעיא אנסתי דלא קא פגים לה דמשלם בושת ופגם על פי עצמו אבל פתיתי דקא פגים לה אימא לא משלם על פי עצמו קא משמע לן

GEMARA. Let it [also teach] “I have raped”! He said that this was not even necessary: It was unnecessary [to state that if a man declared,] “I have raped” in which case he does not blemish her character, that he must pay compensation for indignity and blemish on his own evidence, but [if he declared] “I have seduced,” where he does blemish her character, it might have been assumed that he does not pay [compensation] on his own evidence, hence he informs us [that he does].

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