Ah, I think this is hard. I could honestly see it going both ways. In their 2020 Weekly Idol guest appearance, sgyv mentioned that they usually don’t let fights escalate and resolve issues on the spot. sb noted that bg is very receptive to feedback, and if someone tells him he was in the wrong, he’ll immediately concede, saying something like, “Ah, I can see how I might have come across. I’ll be more careful next time” I’ve also noticed that whenever bg jokingly “scolds” sb or sulks around him, sb apologizes or gives in right away. This suggests to me that, for minor quarrels, whoever is at fault would likely apologize first instead of letting their ego get in the way.
However, during a fansign in 2023, when asked if they were the type to 1) need time to themselves or 2) talk it out immediately when they are mad, bg chose option 1 while sb chose option 2. Based on this, I think if they were to have a significant argument or if emotions escalated, sb would be unable to go to bed angry, while bg might be more inclined to give the silent treatment and need to sleep on it before continuing the conversation.
In general, in long-term relationships I’ve observed, there’s usually one person who gives in. If both people refuse to back down and assert themselves, it’s difficult for the relationship to remain stable. I feel like sb would be the first to initiate a conversation, apologize, and try to make bg feel better. But at the same time, I also see bg as emotionally mature, so if he were in the wrong, I believe he’d also apologize easily, and sb wouldn’t hold grudges.