Not sure about feelings of much younger buddy towards me

Hi. Straight guy here asking for advice...

I am a 32 year old guy who probably never made the full mental transition to adulthood. So far settling down and committing to a family has no real appeal to me. I prefer spending my free time traveling, backpacking, doing sports etc. I'd describe myself as very open-minded.

For the last two years I have spent a lot of time with a now 19 year old guy. I am a very good friend of his (friendly, apparently very caring and functional) family. He is into a lot of the same hobbies as I am. The whole friendship started when I invited him to join me and some other buddies on a camping trip. Now we go skiing, camping and mountain biking together and he comes over to my place regularly to watch movies. (I live alone)

We are very close and get along incredibly well. We help each other out whenever possible and talk a lot about all kinds of stuff and if necessary I try to help him with the struggles young guys have growing up. Also I often mentor him in the sports we do together. It seems he kind of looks up to me. (Subconsciously I myself might be making up for not having kids of my own. I am not sure.)
I really enjoy the time I spend with him. His parents with whom he lives seem to be perfectly okay with it.

So here is the thing: About half a year ago we had one of our regular movie nights. Usually it's just the two of us having pizza and watching old geeky TV shows and movies that not many people are into nowadays. Later that night at some point during the movie when he came back from the kitchen he sat down unusually close to me and laid his head on my shoulder. Since I have always been a touchy-feely kind of guy, I didn't think much of it at the time and just ruffled his hair a little and said to him: "You're a great guy." We sat like that for a long time and it seemed we both enjoyed it.

Since that night wave sort of a bromance going on. When we watch movies together (about once a month) we usually sit or lie close together on the sofa. Usually one of us rests his head on the other's shoulder or puts his arm around the other. We're both okay with it and don't talk about it. Sometimes, when I am at his place sitting on the sofa, he silently lies down next to me rests his head on my thigh and dozes off. All this with his parents sitting next to us. Seeing that I'm okay with it they don't mind him doing it at all. I guess for them it's just a random adolescent thing he does.

He doesn't seem to have any other friends he regularly spends time with except for his 23 year old brother with whom he cuddles as well but much less intensely (at least when I am around). He spends most of his free time playing computer, doing sports (bicycling, skiing. No team sports at all) and watching TV. He is incredibly shy and reserved but once you get to know him and the ice is broken he opens up to you as an incredibly funny guy. He is obsessed with his hobbies and does not care a lot about fitting in with his age group. He is not interested in partying and never seems to notice or check out girls at all. He has never had a girlfriend and when I ask him about girls he says he wants to stay single and that girls are too much hassle, which I find unusual for a heterosexual 19 year old, but it's probably also the reason I get along with him so well. He does not use his penis to think like so many teenagers do. On the other hand he enjoys and occasionally tells very adult jokes and he even has what I call his signature dirty laugh. So he is probably not a late bloomer although he still looks and sometimes acts more adolescent than you generally would expect at that age.

Once his brother jokingly accused him of being gay in some context I don't remember. He did not get offended and immediately tried to steer the conversation to somebody else by responding "No, I'm not but a former classmate probably is. He likes to sniff everybody's deodorant." So there might be a chance that he is in the closet and too shy to come out let alone try to find a so.

Lately I am a little afraid that he might be developing feelings for me. Sometimes when he comes over he wastes no time getting close to me. Once he brushed his hand over my crotch area but immediately withdrew it and apologized although it didn't really seem like an accident, but I am not sure. Then again, he does not seem to get a kick out of all of this. It seems more like he is at peace with him and the world and just enjoys the bonding experience. This is why I'd hate to reject his affections or start any awkward conversations. He really means a lot to me.

What do you think? Am I just imagining this? Is he maybe just seeing me as a father figure and making up for affection he didn't get when he was younger? Am I too concerned? Did I let things go to far already? What should I / should I not do. Do you have experienced or seen anything alike?