Yeah imo it's a bit weird Mok got so many bruises on his body just falling on his own, unless he rolled down the parking ramp or something, but I don't think Nanjo hit him with his car either. He doesn't seem like he'd lie about that and there's no reason to lie since he took responsibility for Mok and brought him to the hospital anyway.
Yes Nanjo let Mok sleep on him for at least an hour and someone noticed he's biting his lips, clenching his jaw in many panels and when I reread that chapter I noticed it too. It's like he's holding himself back and staying still, even tho he wants to do something. About the seafood, Mok prepared pasta with vongole for him at his house but didn't eat it himself and since he doesn't really care about himself even sauce from the bottle will do. I think Nanjo was shocked that he'd prepare an elaborate meal for him and then eat scraps himself. In chap 16 him and Nanjo go out to eat and it's mostly sushi but Mok pretty much only ate egg rolls so in that scene where he seems mad Mok didn't tell him he doesn't eat seafood I think he's just mad because once again Mok is eating scraps because he didn't tell Nanjo his preferences (Mok thinks it's not important but Nanjo evidently sees it differently). Also this is probably just me but I hc that Mok has some sort of eating disorder or extreme food pickiness, where he's basically only shown happily eating sweets and if it's not sweets he pretty much eats scraps (like that thing he said about eating what Sunwha's leftovers). Even when they get burgers he only ordered the complicated thing so he'd be able to spend more time with Nanjo but he isn't shown eating it. Yes on Sunwha's birthday he told Sunwha he was sick as an excuse and when Mok asked he was probably jealous of him lol
Nanjo showed a lot of interest in the date in his second flat as you said and he does come back in the morning to get Mok sweets so that was a really caring gesture too. And YES when Mok rests on his shoulder Nanjo caresses his hair like he does in Mok's fantasy... And he was hugging Mok when they were kissing in chap 40 too, I love that panel where he's holding his head and his waist while they kiss and then pulling his hair too but that's another thing lmao
Another thought for today: So when Nanjo went with him to the hospital, I think the doctors definitely told Nanjo that Mok is malnourished and did not sleep, and maybe that he has scars? Also, what is with the wound on his stomach???? Nanjo said to Mok that he just fainted/fell on his own? Like how??? His head, both arms, and his stomach????? Also, Mok: "You are a bad liar." Nanjo: "You don't know me" => Nanjo, please be not too crazy, just a little bite! I really need the author to show us Nanjo's thoughts. Furthermore, I really want to see his thoughts while Mok was sleeping on his shoulder during the Netflix show. Nanjo literally let him sleep on his shoulder for hours? That hurts like crazy! Also...why was he getting angry when he found out that Mok could not eat seafood? Mok is not allergic? Just because Mok did not tell him and ate the cheap paste sauce, why is he getting angry? Look at his hand and vein? I am starting to think that Nanjo is already into Mok a little bit too much.
Also, he did not sleep with Seonhwa for quite a while >< "HE IS SICK" aha...sure...when Mok asked him how he was doing, what was Nanjos respond "Mok, are you with Seonhwa?" =first I thought he was angry with Mok because Nanjo was still into Seonhwa but now I think he was getting jealous of Seonhwa?
Additionally, we got the scene before the whole I call it the "depressed period" where Mok literally begged Nanjo to not have sex... what did Nanjo do? -.- Jump on him. I think that Nanjo was already into Mok for quite a while... I cannot really define it as love, but he really started to like being with him. Letting him sleep in his second flat, even staying there with him, and also getting him coffee the next day. Hugging Mok when he asked him to. Asking him why he was hurt and listening to him talk about his job. Also, whenever Mok wakes up, Nanjo is not there. Hopefully there will be some scenes where Nanjo is sitting/lying next to Mok and maybe caressing him or something...in some drawings, it feels like Nanjo is thinking something like "Mok is pretty".
Also, I am waiting for some sweet time where Nanjo buys Mok a lot of sweet stuff to help him gain weight.