What (I think) I understand so far:
The most unreal of all realities, set on the boundary that is is neither night nor day. What would be the usual way to call such a thing, or describe it - that I completely forgot. Dusk time is ???, appointed time for meeting things that aren't human.
Without ヶ it would seem something like "(lit.) time of meeting evil spirits", "the witching hour" etc, but what does ヶ add? Is that a play on 刻一刻? A sign that 逢魔ヶ is to be read like 逢魔逢魔 or 逢魔魔 (so that it becomes X刻はA時、B刻限)?
Please correct me if I failed at other parts of translation.