Looks Can Kill (easy ver.)

In the Korean comments

One commenter points to Rei’s styling, writing, in translation, “Rei-chan, this kind of marine look is so, so cute and pretty.” Another recurring touch is Japanese wording rendered in Hangul: “레이쨩 카와이” (Rei-chan, kawaii), an especially playful way of calling Rei cute.

What the words mean

In “레이 언니” (Rei unni, older sister Rei), 언니 (unni, older sister) does not claim a family relationship. It is a casual, affectionate form of address for an older woman.