He is being cautious. He knows both of them are older than they look so he's not really going to hold back in his own way of protecting people he loves. He's not gonna risk it just because a pretty girl he pitied is hurt.
Nonetheless you don't have to worry, just as the Prince has a personality, our FL is not a doormat. All these characters are well written in the novel. Hopefully the manhwa stay true to it despite a lot of changes I've observed
What has changed in the manhwa? Tbh the manhwa is kinda boring imo, if the novel more interesting i'm thinkjng of reading the novel only instead.
There's a lot but a notable one that was supposed to happen before this scene was that FL and the prince have met face to face already before this secret meeting. With the siblings as witness though.
The novel is much more introspective of the character's thoughts, specially FL and the Prince. You might enjoy it if you want to see depth in their characters. The manhwa is much more simpler in my opinion.
Tf? This bitch stopid and tf you're supposed to be older tf? The prince can't think for shet