Eating quietly and then Make It Hot

Why Koreans care

The title's 밥 묵다가 (bap mukdaga, while eating in dialect) uses a dialect form of eat. Alongside the song title, this everyday wording presents the dance as a casual interruption to a meal.

In the Korean comments

Casual-outfit admiration appears in “I like a man who shines even in an undershirt and mint-colored slippers” (fandom). The guest's dancing is another focus: “GGONDAEHEE dances so adorably” (fandom).

What the words mean

Calling MINHO's looks in an undershirt 반칙 (a foul; figuratively, unfair) is affectionate mock protest. The commenter means he looks good without dressing up, not that he broke a challenge rule.