from this chapter alone:
1. Cristea met the prince First, THEN she contracted Kurogane and Mashiro (around chapter 80-100 cmiiw)
2. The prince is not a huge jackass. Here he was saying things like "Show me your bad food. I will put you in your place!". In WN he was instantly captivated by her, thinking like 'there's a fairy standing in front of me' but Unintentionally called her 'repulsive food eating lady'.
3. In WN he didn't throw the food, this is the point that is most disagreeable to me, like, WTF??
in short, the story here is massively shortened, the sequence of events is shifted (these alone is fine by me and happen quite often with adaptation). But the character trait of the prince is just different altogether