Docile Tomari is love. <3
As for the demographics conversation, GFantasy published the likes of Black Butler, Nabari no Ou, Horimiya, etc., and this fits right in with the overall style. The editors at Square Enix's Gangan Comics (which GFantasy is a part) have never been afraid of cute things, androgynous things, pretty boys and pretty girls (and bloody things--it's not all sweetness and light). I wouldn't be surprised if these magazines have many more female readers than a supposed "shounen" imprint is supposed to have.
So if you ever find yourself thinking, why is this cute comic technically shounen, it's probably something from Gangan. Good for them. I love their style.