Jungwon studying is too cute!

In the Korean comments

One top comment reads, in translation, “The way Jungwon writes it as ‘Jjongsaeng,’ hahaha.” It catches the playful spelling 쫑생 (Jjongsaeng), a twist on Jay’s Korean given name 종성 (Jongseong).

What the words mean

The ending 잖아 (jana) literally points to something the listener already knows, but here it works as a lightly scolding reminder: “Come on, Jungwon is studying.” In 쫑냥 (Jjongnyang), 냥 (nyang, meow) turns the name into an affectionate cat nickname, matching the comments that compare Jay with a black cat.