Some people say that Kibahina won't ever happen because they view each other as brother and sister. I know that Hinata probably sees Kiba that way, but what about Kiba?

+"If you get that sand guy forfeit immediately!! The only guys remaining are you and Chouji, Neji, Lee, the sound nin and the sand guy. Listen Hinata ... and one more.. If you do get Neji then do the same forfeit. He's cruel to you ... you'll get beaten to a pulp"
This practically says that he is concerned with her health and/or life. He doesn't want to see her hurt.

But then when she does end up getting Neji, Kiba says the cuss word equivalent to "dang".

+When Kiba and Hinata were watching the chunnin fights, he had saved her a seat beside him.

Awww :3 so sweet of him! What a perfect gentleman *snicker* (usually Kiba isn't a gentleman but he is to Hinata! ^^)

+During Naruto's and Neji's fight, Hinata starts coughing up blood.
Hinata: *cough* *cough*
Kiba:! Hey are you alright?!
...(3 pages later again)
Kiba: *big exclamation* ! Hey Hinata you're bleeding!
Hinata: No naruto no more (Naruto was getting beat up by Neji the same way she was before :/ )
Kiba: The damage from you fight hasn't healed yet!
Hinata: *cough* cough*
Jounin dude (forgot his name XD): What's wrong?
Medical Anbu (who is actually kabuto): I'll take a look
Kiba: who are you?
Kabuto: well I'm no one suspicious
...(1 page later)
*Kiba is staying by Hinata's side while Kabuto checks to see what's wrong.*
(chapter 102 page 2)
Kabuto: *starts healing Hinata*
Kiba: Hey!
Kabuto: Don't worry I'm a docter
(chapter 103 page 8)
Kabuto: *done healing Hinata*
Kiba: !!! thinks : Life has returned to Hinata's face.