Someone still writing the most embarrassing trope of them all "hearing just the worst part of a sentence than immediately leaving the scene" with a straight face in 2025 is really fascinating. Romcom authors are really creatively bankrupt.
Ah the classic japanese trope of an eavesdropper running off before hearing the full story so that at the very least a dozen chapters of filler can be made
Eh should wrap up fast since the supposed "girlfriend" is already talking to Sou. Things will likely be cleared up and the other girl will figure out real quick Sou's feelings.