Well, in the Breath manga and its anime, one noticeable thing is the character expressions. Sometimes in the anime, they might be more exaggerated for effect. But in terms of the story, they're pretty similar.
Well, invisible sex comics usually play with ambiguity and suggestion. They might have characters' expressions or body language hinting at sexual situations without showing explicit acts. The storylines could also imply sexual undertones through the context and interactions.
It's hard to say. Could be that Adam discovers an ouija board in a comic and some mysterious events follow. Or maybe it's just a random combination with no real connection.
Drawing stress comics successfully involves capturing the essence of the emotion. Try exaggerating features like wide eyes or clenched fists. And play with light and dark to emphasize the stress. You can also incorporate symbols or objects that are commonly associated with stress, like a ticking clock or a mountain of work.