Eun-Seol, who always took care of me and played with me when my friends didn’t play with me because I was sick. The problem is that even when you become an adult, you treat them like a baby. In the end, even when I came to college, the nickname ‘Bae-dung-i’ spread and became an outsider. Now, even if you look like a man to your sister, you have to get away with treating her like a child.(Source: TOPTOON, translated)
Note: Chapter count includes an epilogue