Of course they are. It's iyashikei with two girls - spicing it with at least subtext is obligatory.
Other than that overused "trope" (which at this point, after seeing it done countless times in countless series, i really can't consider being anything else than marketing device to expand readership base ; thankfully it doesn't cheapen the experience here - just pointing out general pattern) it's great. Especially art, and super especially when there are color pages.
...just for fun, contrast this series with "Beautiful Darkness" by Vehlmann and Kerascoet.
Thanks for the update!