Am I right?

Im 18 and my little sister is 16,

She’s in her first year of college and has had her first kiss from a boy who is 19.

He gave her a hickey on her boob in college the other day and I’m really not happy about it, he also was texting me thing like ‘I’m a beast, I’m going to put your sister in a wheelchair’ (in a sexual way) as a joke.

I didn’t find that funny and had a chat with him face to face,

My sister tells me everything and he said I’m getting too involved...

She’s my little sister and I’m gonna do whatever it takes to protect her and lead her the right way....

I don’t want them to talk anymore... am i wrong for saying that???