No.1639
Personally, I think he represents Madotsuki's r̶a̶p̶e̶ loneliness, which is kinda a major thing in her life, especially if she is indeed a hikikomori. Onsen-san is alone in his room (I guess it's his house if it's only one room but whatever), in the dark no less. The area around his house, the Wilderness is ENORMOUSLY empty. The only thing in the area that moves is the towel, which is more like a blanket, considering the way that Madotsuki looks when using the effect (she wraps it around herself and she sneezes as if she is ill). Children generally hold blankets when they're scared or cold, which is what Onsen-san probably is, seeing as he's alone, "crying", and sitting next to a hot spring. Plus, Onsen-san might be trapped in the house, despite the door being open; when you stab Onsen-san, his head turns blue and he stops sucking up the hot water. Looking at Onsen-san, his head/head-tube are a bright red. Then his body is a dark red/green. Then, his legs are blue. Maybe the reason he's sitting down next to the hot spring is because he needs the warmth to live, and the only way to keep warm is to keep supplying his brain with the warm water of the spring. He can't move because he couldn't supply his legs with the warmth they need and thus died, hence the blue color. His body and his heart are on the verge of dying, as he can barely keep it warm with the water from the spring. He might represent Madotsuki's need for "warmth" to keep herself from dying; warmth often being another word for kindness/love/etc. The spring/hot water represents the "friends" that Madotsuki has made for herself in her dreams, which are her only source of "warmth" in her room. Onsen-san's dead legs represent Madotsuki's own inability to leave her room. Onsen-san's nearly-dying body represents Madotsuki's want to end her imprisonment. The tube connecting Onsen-san's head to the hot, sustaining water represents Madotsuki's dreams connecting her brain to the mentally sustaining "friends" she meets in her subconscious.
Once the hot springs run out of water, Onsen-san will have no more source of warmth and will die. Once Madotsuki meets everyone in her dreams, she has no more source of friendship/love and dies.
No.1640
I for one can't ever see Onsen-san the same way after seeing this picture in the archives.
I do think you're right, that he's supposed to be alone and isolated, and I also agree that there's some kind of temperature indication with him, in the way that his head that's sucking up the hot water is bright red, but his legs are a lifeless blue? So I can see the way you're thinking in that Onsen-san is a parallel to Mado staying in her room. I can also most definitely agree that the Wilderness is a representation of loneliness; the event with the Toriningen having a party seems like it has a very similar theme, in that while the Toriningen are having fun together, Mado can't join them. She can only watch them.
The thing that I disagree about is the idea that Mado wants to end her imprisonment. Onsen-san might be sad, but is he really sad about where he is now? The Hot Springs area seems very kind and peaceful, to me. The music is pleasant, the surroundings aren't nearly as threatening as in other areas, the darkness in the room almost seems like it's conducive to sleep. I see Onsen-san as someone who's upset about something, and is hiding away in here to comfort himself and stay safe, like Mado is by staying in her room to hide from the big, scary world. If he left, then yes, he would die, but it's not so much because he can't live without the water, as he can't bring himself to gather the strength necessary to live in the outside world. It's his own damn fault that he can't leave his room, not his legs/the water/the outside world's!
This kind of "I can't go out because <x>" rationalization is basically what I see as being the cause for all of Mado's suffering. Like, these factors certainly aren't helping them go out and face their problems, but it's their own fault that the problems are there in the first place. So I guess all the facts about our theories are the same, it's just the morals behind them that are different. :s
No.1641
Well, theories are theories, so who knows. I don't feel like Onsen-san is content because of the black streams on his face, but on the other hand I didn't make him so I don't know if they are tears, or veins, or whatever.
In hindsight, however, it makes more sense that Onsen-san is happy to be in his room, alone, considering how horrific the outside world can be. Hell, that makes him even more relatable to Madotsuki, hiding in his room in fear of what's outside.
The point is, though, that I feel Onsen-san deserves to be examined and looked at just as often as the other strange, random characters, like Monoe and Monoko, KyuKyu, Mars-san, etc.
(plus he seriously deserves to be more well-known than that zombie kid in the road is)
No.1647
I just played for a bit to take a closer look at him, and I didn't notice before that his mouth moves slightly. I'd actually say it appears to be slightly switching between a frown and a smile, or perhaps denoting that he's muttering something to himself? Either way, I'd say that it denotes him feeling some kind of conflict.
If you're right, and the lines on his face are tears after all (And I'd say they are.) then maybe there's some kind of connection between his tears and the tube going to his head; namely that he's siphoning off water to become his tears? If this is the case, then I think I might be able to vaguely connect these two facts:
Onsen-San is a pitiful, conflicted thing/person who is responsible for his current state of being, with his limbs atrophied and incapable of moving, leaving him alone in his dark room. At some point, he started siphoning off water to allow himself to cry. (Or rather, to make it so he can feel bad about himself.) This addiction to self indulgent misery is what led him to where he is today after he continued doing it for so long that he could no longer muster the strength to go back out into the world, so now, he sits, still crying and suffering through the mental conflict of wanting to leave and go back out into the world, but not being able to stop feeling sorry for himself long enough to do so. He's a manifestation of a never ending hesitation, and pure indecision.
This represents Madotsuki in that she's staying inside *her* room, scared of the outside world and feeling sorry for herself. Unfortunately, the longer she does this, the less prepared she is to return to the outside world and confront her problems.
No.1648
Derp. And I forgot to connect it to some other points about the area, some of which are similar to what you said:
-The Wilderness Area is focussed on Mado's loneliness and depression. It seems rather desolate, in that the plants that grow are short, simple, and more like vines than trees, like the area can't support much life. Like you said, there's very few NPCs around, other than a towel, which seems like its purpose is to comfort Mado and make her feel better. Still. It's not much of a companion.
-You have the Toriningen Party in the area, which I've speculated before is about Mado's loneliness, since she's not able to join them.
-Lots of sad frowny face blocks everywhere. :(
-The Barracks exist on the outskirts of the area, but are generally fenced off from Madotsuki and not particularly welcoming. The NPCs here seem human-like, but are very unrelatable to Madotsuki; they're identity-less, with holes for faces, and show no apparent emotions. (As opposed to NPCs like Monoko, Monoe, and so forth, who appear much more human, at least for a time.)
-Trying to think of the symbolism of the curled plants with red eyes that appear around the stairs to the Sky Garden, I think they might just represent the general paranoid "I'm being watched" theme that's prevalent throughout the game.
So yeah. I think this interpretation of Onsen-San could connect quite nicely.