I'm doing my homework;; - You're speaking informally to me...

" ..It's my sister!"

Seongho goes to Yeoju, looking at you doing your homework.
It's coming.
And stand in front of the heroine.

"What are you doing here, Unnie? Hit."

"Just... homework?.."

"It doesn't seem like just homework?"

"It's noisy, so get out of here."

"That's too much... When did you ever do your homework?"

"Hey, do you want to get in trouble?"

Yeoju gets angry at Seongho's words.

"Haha, you're so funny, sis."

Seongho watches the user do his homework and then leisurely leaves.