Sforno on Genesis 34:3/ספורנו על בראשית ל״ד:ג׳

1ותדבק נפשו, this was the opposite of Amnon having raped Tamar whose infatuation with her turned to disgust the moment he had satisfied his biological urge. (Samuel II 13,14-16)

2בדינה בת יעקב, because she was the daughter of the widely respected Yaakov, someone of an international reputation. The Torah confirms this once more later in verse 19 when it describes Shechem as desiring the “daughter of Yaakov.”