Hold up...
Holding hands to prevent separation in the crowd is one thing, but holding hands even at the water balloon stall... that's a total dating couple move! They probably just didn't notice and there was no one to point it out (or people here are just considerate like her sister - though it's kind of a jerk move to walk in between a pair of people who are so obviously coming together though, so, I'm not so sure about that; at least you can just walk around them?)
Mangaka-san has 8 assistants and 2 editors? Manga really is a team effort
Look at all the details, I guess that make sense?
EDIT
Oh wow...
I never paid attention to author's page in MD that much, only know he had another completed series on the site. I went there today to see if he had another serialize running to justify 8 assistants and 2 editors, only to notice the parentheses on his twitter link...
