Advice for a guy with a (potentially) Gay friend?

I'm a 25 year old guy and I've got a pal who is also 25. We get along really well and have a lot in common, but recently I've started to think that he might be gay or bi. He doesn't have any stereotypical mannerisms and I haven't caught him checking out any guys (yet), but sometimes he will let off little "hints" such as random things he says or does that make me wonder. At the same time it could just be him being a sarcastic goofball, which he is, but I'm not really sure... The fact that he's never had a girlfriend for as long as I've known him despite the fact that he's not bad looking or cheap or anything and his parents/friends are always trying to set him up with women does not help his credibility, either... Anyway, his parents are the hyper-conservative homosexual = sin/death/destruction-type, so I can understand if/why he would want to hide it. His orientation doesn't matter to me one way or another and I'll always be friends with him no matter what, but if he happens to actually be completely straight-laced I don't want him to think I pegged him as a queer and screw up our friendship or anything. I'm not asking how to find out whether he is gay or not. I just would like some advice on how to say "I'm here for you and you can come to me for anything", subtly, without making it sound so... emotional.