I enjoyed this series too. It was quite comforting to me.
Sosuke's brother essentially dies b/c he went in to see him and he shouldnt have b/c his brother was in a quaratine/isolation room. Sosuke didn't do the required cleaning one would have to go thru to see a person like that. He didnt even wash his hands when he went in. So he felt dirty/unclean b/c his germs in his mind killed his brother. Even though the brother was terminal Sosuke's visit exaccerbated his condition.
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Sosuke's brother essentially dies b/c he went in to see him and he shouldnt have b/c his brother was in a quaratine/isolation room. Sosuke didn't do the required cleaning one would have to go thru to see a person like that. He didnt even wash his hands when he went in. So he felt dirty/unclean b/c his germs in his mind killed his brother. Even though the brother was terminal Sosuke's visit exaccerbated his condition.