Just imagine a scene where a villain figures out that strong emotion can affect Goku's ultra instinct and so he starts attacking vegeta instead to try to make Goku upset and at first vegeta is like "HA you think hurting me will affect Kakarot at all? Fat ch - kakarot?"
And he looks over to Goku who is now in base form because he cant contain it and hes angry and cant help it.
Honestly outside of the first couple of chapters where they flirt a bit, Inuyasha and Kagome’s relationship always struck me as more of a brother/sister thing so I honestly never understood why everyone both in-universe and in real life assumed they were in love
But apparently they did end up together so shows what I know