I think about these two alot and how interconnected their lore is from a storyline standpoint. They're absolutely toxic for each other because all Kado does is fuel Angel's violence whenever he's threatened. He does nothing to try and teach him that that's not good or even tells him that he's not doing the right thing. Angel doesn't even know it's bad because he was never taught about something like moral boundaries. All he's ever known is to fight to survive (lore).
Not to mention the fact that now Angel is most definitely needing Kado's help for solving the current issues that are happening which involves his past which he himself doesn't remember. Yet Kado does. He knows about the time loop but chooses not to say anything. Now, Kado isn't evil he also just doesn't know how to process emotions like loss, anger, fear etc. But he's not a saint either. Just something to think about.
C!Angel and C!Kado are mine.