@NinjaGoemon Not particularly, but touching another girl's hair without asking permission isn't nice. It's getting a bit intimate and invading their personal space. It's easy to see how a sheltered ojou-sama could misinterpret it as a gesture of romantic affection.
Luna & Koihime asking the important questions in life:
This is funny and adorable, but I hope it gets to more than simply teasing and their relationships develop, although for a manga like this, idk, but I like the charas.