I don't follow PF, really, so I'm unsure of the identity of the hugger, here. Another Orie, I would guess, but I don't have a name for her.
EDIT: I'm an idiot and just now read the Hiragana. Guess her name's Mitsugi, but I'm unsure if/how she's related to Hakua.
They're sisters if I remember correctly, Hakua's little sister and looking on Twitter I thought I saw her under the name Setsuna somewhere. I could be wrong but I'm pretty positive they're sisters since there's been a few pictures of Hakua's parents with an infant version of Mitsugi/Setsuna in their mother's arms.