In this anime at second 0:38 the main character is justifying why he accepted a fight. https://animelon.com/video/57a81215b9de7414d1ea082d
In the context of the situation it sounds like he is saying something along the lines of: I was carried by the emotion of the moment. or I didn't think about it back then.
However, all the translations I find on the internet are something along the lines of "tit for tat".
Can you please explain how that fits in this context? Or maybe there is a more nuanced meaning to this?
Also, do you have a nice explanation how "The sold word becomes the bought word" makes the jump to "tit for tat"?