Welcome! You are very brave to have entered and continued a relationship w/ him after finding out he is a JW. From personal experience, and I hate to break it to you....but, this relationship will not last forever. I was raised as a JW and the first guy a fell in love with was "worldly". My parents found out through some of my closest "friends" at the KH. The freaked out. I was then labeled as bad assoication. As will your boyfriend if your relationship becomes public knowledge.
My question is: Is he baptized? The reason I want to know is, if he's 20 y/o, and he's not baptized yet, that may be good for you. Most JW youths are baptized well before their 18th b-day, if they are "spiritually minded". If he is, then just WALK AWAY. Should he decide to be with you, he will lose his entire "life" i.e. family, friends, and love. MOST, but not all, JW's show conditional love and teach conditional love, that is how those who are raised in it stay in it, for fear of losing all they know. That is a very scarey place to be, so until that person is ready to enter the reality of losing EVERYTHING they've ever known, you may be SOL.
Just a sidenote.... I was 18 when I married my 1st husband, who was/is a JW. It only lasted a few months before he became violent with me, and when I went to the church to seek help, they told me to be a "good wife". Thanks to him, I began to see how a$$ backwards these people are. Long story short: We divorced after 3 years of marriage, and 1/2 of that time he lived with his parents. Unfortunately, we were too young and immature to be married, and adding in my independent thinking, the marriage was doomed.
On a happier note: I am married to a wonderful NON JW man, and we'll be celebrating our 4 year wedding anniversary this DEC!! We also have a beautiful daughter who is 3 and will NOT be held back and stiffled by the JW cult.
Think long and hard about what all of us "strangers" have told you. We don't know him or you for that matter, but we know the organization and what it does to people's lives. You know the old saying "when in doubt, do without". Good Luck to you! :)