Personally, I don't think he's very creepy, but yeah he is antisocial. Near is a pretty subtle character and has some downright unlikeable traits, but I love them because I love his character.
Near is a pretty hard person to pin down, and what with his attitude, not many people try, but, honestly, he's a vulnerable antisocial fuck. He lives in his fantasy toy world. It's also a bit easy to get under the boy's skin; he acts incredibly rude when something gets to him.
But, he is also capable of affection and human compassion. Hell, in that oneshot, he had those fucking finger puppets practically glued to his hand. He was stacking cards with them on. The boy obviously had an attachment to Mello and L and I can point out pages that reveal this if you so desire.
Near also has a lot of pressure on him to succeed L's title. Before him was:
A - committed suicide because the pressure to succeed L was too great
BB - another successor who went fucking nuts and became a serial killer
Mello - killed
Matt - killed
The original L - killed
I can't help but feel that succeeding L is something he's only really doing because he's supposed to and it's incredibly awkward process for him. Even in the one shot he's like, "Maybe I wasn't like L..."
Fuck, I love the shit out of him. He's just so beautiful, intelligent, and moe.