I think you misunderstood what I said? I think that his behaviour isn't adorable, because It's a consequence of a really messed up situation. You haven't said that the manga is adorable, but that his behavior is, and It just rubbed me the wrong way after reading this manga. I'm calm, just expressed my opinion
ADHD is not categorised by impulsiveness, and it’s actually really hard to diagnose so please don’t say things like that because they’re incorrect. also, did you forget that shigeru was pushed off a cliff and got severe brain damage? he can barely talk, or take care of himself because of that. he’s nearly 15 years old, it’s actually sad not cute.

Shigeru is so adorable! He was acting like he was possessed in this Chapter. I don't know if this is a dream or not because his parents are constantly by his side taking care of him. He wouldn't be able to leave without them knowing. I think Shigeru has ADHD because he is impulsive...dangerously impulsive ( he almost pushed his cousin off a cliff, he was playing too close to the edge of a cliff, and he wants to play during a snow storm) and he doesn't listen to simple instructions.