Your presence in his life is everything this man asks for. Even if he knows he doesn’t stand a chance with you, he’ll patiently wait for you to let him all in.
And, until then, he’ll settle for being your friend. After all, it’s better than losing you for good.
If this sounds familiar, I’ll just give you a piece of relationship advice: don’t drag such a nice guy along. Don’t use his kindness, and don’t take him for granted because you might regret it.