Most Helpful Guy
You don't try to get it any further, let him feel safe, take good care of him, be patient and he will come to you eventually, he wouldn't be around you knowing that you like him unless he likes you too.1
Most Helpful Girl
Honestly my advice is to be patient and understanding. If he wants to have sex (or be intimate) and is just intimidated take things slow and build up his confidence.. as he gets more confident he will be willing to try new things and do more. We were all there at one point or another, some people are just more nervous about it than others. Some people just need someone to show them the way and guide the way.
Have you talked to him about it? That might help you understand where he is coming from.3