Consequences of an 18 year old male living with 16 year old female?

Use birth control, or a likely consequence would be an unwanted pregnancy. Even if the two of you would like to have children together, it's too early for that, give it a few more years at least.

There could be lots of other consequences. Doubtlessly there are some people who will disapprove of such a living arrangement on the grounds that the female is still a child. But it's your life to live. If you can pay your own expenses, you are beholden to no one.