Under HK law, it is legal to visit a walkup girl (141 Classic) who has a HKID -- provided there is
no more than one girl working in the room/flat at the time.
Almost all hotel reservation girls (HGs), and increasingly walkup girls as well, are PRC residents
working in HK illegally on short-term visitors' permits. Technically the transaction is illegal anyway,
so it really doesn't matter whether it's 2P, 3P, 4P or MoreP.