A 12-year old girl is sexually mature and can safely have sexual intercourse with a 40-year-old man. A 4-year-old can't. That is the difference. Nathan was completely honest about his intentions towards the girl. Both parties knew exactly what the other person wanted and when. There was no manipulation involved at all.
I know that engaging in sex with a minor is classed as statutory rape regardless of whether the minor is sexually mature or agreed to it as they are deemed to lack the capacity to give informed consent, but that doesn't change the fact that attraction to any female from the onset of puberty to menopause is fully normal and healthy. The legality and social acceptance of adults having sex with preteens differs across the world,
but it's normal to want to have sex with girls of that age.
More likely than not, nothing horrible would have happened to her if Nathan did have sex with her. A 12-year-old girl is actually more likely to have a positive first sexual experience with an adult man than with a boy her own age.
"Rind and Welter (2012) examined reactions to first postpubescent coitus, an especially significant life event. Hebephilic first coitus (i.e., girls aged 11–14 with men) was just as positive (17 % of cases) as woman–man first coitus (18 %), and was significantly more positive than ephebophilic (i.e.,girls 15–17 with men)or girl–male peer first coitus (both at 12 %). Moreover, hebephilic first coitus was no more emotionally negative (18 % of cases) than woman–man (17 %), ephebophilic (17 %), or girl–male peer (20 %) first coitus."