Need help!

So my dad has 4 kids. Me my 3 sisters and my brother. My sisters and me have the same mom and dad. Our brother (hunter) has the same dad and different mom. Hunters mom has another son (Kyle) with a different man than our dad. Me and Kyle like each other and we've kind of been talking about a relationship and we've gone on a couple dates. Is this okay? Or is it wrong? Seriously need the help. And opinions and comments welcome!