Is Biblically sin, if between a girlfriend and a boyfriend?

I am asking this because my bfd and I are Christians of different religious backgrounds. I believe Biblically outside marriage is sin and he agree with me on that. But he believes that is not sin since it is not.He wants to roove it unbiblically which I don`t agree. He wants us to with each other which I consider it immoral. We have been dating for a year now, and he is relactant to take the next step. Is he afraid to commit or he is satisfy with materbation as he approoves of it? I am fade up of too longwaiting for him to take the next step because I made it clear to him what I want. Instead he want to move in with me as co-habiation short of relation whereby we either until we legally get married or what I don`t know.I also refused because I can`t move in with a guy before we are married.It doesn`t make sense to me.Can somebody out there help me what this guy is really realyy after?I am confused because I am about to tell him to back off!!