You'll melt at Juun's smile too

In the Korean comments

The ending is the moment to watch: one comment reads, in translation, “What was that at the end? Why is she so cute?” Another says the final expression is cute.

What the words mean

“아빠미소가 절로나오네” (appa misoga jeollonaone, “a dad smile comes out by itself”) does not literally identify anyone as a father. It affectionately describes an involuntary, proudly delighted grin prompted here by the ending.