I think it wasn't out of nowhere, honestly he has been pretty immature but he has always said to break up with him, which was dumb since he could do it himself, but if you look at it from another perspective he still wanted to break up despite feelings of loving him or their past together, he was impatient and immature and waiting for the axe to drop, so when it finally did he didn't have any qualms about it and let it happen, again he still could have done it himself, but the breakup wasn't bout if maturity but relief.
I think it’s because when breakup was just a prospect, it was scarier than when the reality kicked in and he could finally just admit to it
Coz it’s scary to go into it one sidedly so it’s better to try and make it last but it was obvious that he had that mentality from the beginning of the story—
I think anyways!
Lol......his maturity came out of nowhere, did he get possessed? Also YECHAN LOOKS SO MF FINE IN THAT SHIRT STAHP