Due to some circumstances a guy brings a girl to a hotel in order to loose some pursuers. In there they get swept away by the situation and end up doing some foreplay. The girl ends up fainting halfway and after she wakes up they leave the hotel and the guy apologized for getting carried away. Then the girl responds with this (the 3 hours below is the time she lost consciousness)
What I don't understand how the なきゃ used in this situation
3時間だっけ? アタシが寝てるあいだ、なにもしなかったんだろ?」
「無抵抗のときはなにもしなかった。 アタシがブッ飛ばしていい状況でなきゃ変なこと しなかった」
「この点を誠意と受け取っておいてやる。 あやまらなくていい」