I came across the phrase which I wrote in the title while reading a manga and I don't get it very well. At first I thought it was actually 言い訳 and the author didn't want to use kanji but after reading a few examples when I searched sentences, it's actually 良いわけない, so it would roughly translate as "That's no good"? Let me give a little bit of the context.
It's about two teenage boys and they have magic powers. Let's call them A and B. Each boy can summon a magical weapon. A is a better magic user and can wield his weapon very well while B is less trained, but at least he can summon his weapon. B asks A to train him.
*B summons/takes out his magical weapon and A says the following:
これ実家で保管してるやつでしょ？持ち出しちゃってよかったの？ (Is he saying "This the thing that is kept in your family, right? Isn't great that you can bring it out?")
I know it's a very rough translation...And now B replies with:
So, I get the last part ("Hurry up and teach me how to use it!'), but the first one, I feel like he wanted to say "this isn't good" or even 'good enough'. It's just this small part that I need to know to understand something in regards to their powers.
Can someone help me out, please?