[Her body goes rigid, and at first she doesn't kiss back. Her first kiss, something most Japanese girls treasure. She feels no sense of loss, though.
Finally, once the shock passes, her lips soften and become more malleable. She still doesn't know what to do, but she's not actively resisting now. She feels like she wouldn't have the strength even if she wanted to, like something vital inside her has given way. For better or for worse, this is happening.]