what does 「甲斐無しの夜に」　mean? I think it translates into [Kainashi no yoru ni]. Im guessing something like...on a worthless night? can someone help me, no one is able to give me a better understanding on the saying...and explain to me why it is what it is please? thanks!

also help with this:
Kitsune Wa Mukachi No Uta? i know that kitsune is fox and uta is song i thing but im not sure where mukachi fits in..im bad at understanding sentance structure =/