One of the most misunderstood words in Japanese is 訳（わけ）. Of the many ways it can be translated, the most common are ‘reason’, ‘cause’, ‘meaning’, or ‘conclusion’. Despite this, it may be beneficial to consider it almost identical to an equally versatile English word ‘so’.
In all of its uses, わけ simply highlights the plain existence/determination of something in the same way that ‘so’ does in English. This can be seen in its most basic form in わけだ
. A combination of わけ and the 助動詞（じょどうし） (auxiliary verb) だ
will be used at the end of sentences, and is sometimes preceded by という. This use is often translated as ‘for the reason of (A)’, ‘no wonder its (A)’, or ‘its (A), as you’d expect’. Realistically though, it just means ‘it is so that it’s (A)’, or ‘so it’s (A)’.
The train was late due to an accident? So that’s why you came in unusually late.
You are saying that my finger was broken? So that's why my finger hurt when I moved it.
As I expected, you didn't practice at all, did you? No wonder you haven't improved even after a year.
Today is a holiday, isn't it? So that's why they are closed today.
Due to わけ being a noun, it will need to follow the 連体形（れんたいけい） (attributive form) of whatever word comes before it. As we can see ‘so’ and わけ have an extremely close pattern of nuances, ranging from ‘because’, all the way through to simple emphasis (like with ‘naturally’, and ‘as you’d expect’).
わけ may also be used in questions, implying that the speaker is trying to determine something that they have heard. わけだね ‘so its (A) right?’, and わけです
か ‘so is it that (A)?’ are good examples of this.
So you are saying that you don't want to be with me, right? I understand.
Senpai, so will you be coming later?