When bored.. #BOYNEXTDOOR #ANIMAL #ANIMAL_Challenge

In the Korean comments

The comments supply a rewatch cue absent from the captions: one reads, in translation, “You can see Seongho mouthing ‘What are you doing?’ perfectly.” Another makes a mock-urgent request to reveal Han Taesan’s phone gallery “for the public interest,” treating this strange clip as a glimpse of more material he may have saved.

What the words mean

공익을 위하여 (gongigeul wihayeo, “for the public interest”) normally sounds formal and civic-minded. Here it is playful exaggeration: the commenter jokingly presents access to Han Taesan’s phone gallery as an urgent matter of public benefit; the question mark signals the joke.