Boyfriend Moving Into My New Home

Im a new home owner in Texas and my boyfriend is moving in with me. It's a long term relationship and we don't plan on breaking up, but I never plan to marry or combine any of our assets. My concern is if guess squatters rights? I dont want there to be a chance he tries to claim possession over the property in anyway. I dont think he would, I've just always been paranoid and very protective over my things and what I've worked for.

Is there a basic contract template that would outline that he never try to pursue any ownership of the property or maybe an attorney who could draw one up? Just something to cover the basics. Thanks