To me southern Slavs are Slavs. I don’t know ethnogenesis of your people in details. Sorry. Here, in Belarus, Poland, Ukraine, central Russia we are Slavs. There’re regions such as northern Kazakhstan, the Far east of Russia, Transnistria, Caucases, where there are Russian speaking people. But if you look at their roots closely, they have different ancestry. They don’t have traditional culture and history in their respective regions similar to our.