Is there such a thing as friendly but very shy guy? How do they show their interest?

Wow, this sounds a lot like me :P yeah, guys like this exist. The thing is, if he hasn't had many relationships, he might take a while. It takes a lot of courage for guys like that to choke up the courage to really show their feelings. Some things that can help are just striking up a conversation with him. Make eye contact, smile, but not too wide, and be as close as possible to him without making him awkward. A lot of guys are worried to make a move unless they think you have feelings for him too, so you have to be really obvious because some guys will take what you think are hints as meerely signs of friendship (seriously, we're totaly dense). I'm not talking about hanging off him or anything, but show him that you have a definite interest, and if he likes you, he should perk up. Good luck, and i hope it works well for you! :)