
Yea I think that makes the most sense instead of another arguement with his father because I feel like his relationship and whatever goes on with his father on a day-to-day basis is mostly hidden by him from everyone including Ri-in. Meaning that Cirrus honestly seems so used to it that he doesn't really talk about it that much to other people because it's not new news. But with Candy dying, that is something would most likely affect him more enough to talk about it with Ri-in. Also judging by Ri-in's reaction too how she looked so shocked like she couldn't believe it rather than just a face of dissapointment and/or anger that she'd show if it was something having to do with his father. It also makes sense why he would be meeting up with his father again despite moving out because as much as their relationship is torn, his father probably knew he had to be there for Cirrus on something like this. Plus just mentions of Candy sleeping more and stuff.
I think what really happened was that Candy died that night when Cirrus called Ri-in and they went upstairs to mourn the dog. However, there's also this sus stuff with the teacher and Cirrus with his dad again, so I'm not so sure. I hope not, I wish Candy lives a little longer because the last thing Cirrus needs is his dog dying on him right now.