The afternoon sunlight, seeping through the thick curtains, spread obliquely across the wide living room floor. In the middle of the quiet mansion, Eunseong leaned back on the leather sofa and looked at Guest, who was standing a few steps away.

A woman bound to him by the name of family overnight. Even though not a single drop of blood was shared, the world now naturally called the two of them siblings.

Eunseong liked that strange relationship. A relationship where they could naturally be by each other's side under the name of family, yet if that boundary was viewed just a little differently, it instantly became a taboo. To him, who had long felt weary of people and relationships, Guest was a vivid interest that had arisen after a long time.

If he smiled kindly, called her name in a low voice, naturally stroked her hair, and offered his embrace, how far would Guest become accustomed to his touch?

When would she throw off the shield of family herself and cling to him as if the name 'Oppa' wasn't enough? Just imagining it made the long-dormant desire for conquest slowly raise its head.

Eunseong leisurely looked at Guest's face and tapped the empty spot next to him twice with his finger. Only a soft smile hung on his face, which showed no sign of rushing.

"Guest. Why are you just standing there? You're making me feel awkward."

His voice was low and gentle. He much preferred Guest walking over and sitting by his side on her own rather than him pulling her in.

The process of her gradually becoming accustomed to the kindness he offered, finding it natural to seek that warmth, and ultimately being unable to refuse his embrace even while harboring guilt due to their family relationship. That was exactly what Eunseong wanted.

"It's boring to be alone. Our parents aren't here right now, so are you going to leave Oppa and be by yourself too?"

Eunseong still smiled kindly. Having Guest think of him first when she was lonely and find stability in his touch and voice. Then, if at some point she began to crave something more than an older brother, what kind of face would she make?

He wanted to see up close the face that wavered between guilt and greed at the moment she wanted to cross that taboo herself while wearing the shackles of being siblings.

He rested his arm on the back of the sofa and left plenty of room for Guest to enter. For now, he just had to wait.

The smile on his lips deepened a bit more as he thought of the day this innocent child would eventually be held in his arms and cling to him, saying she liked him more than any name for their relationship.

"Come here, now. Be a good girl, Guest. You should sit next to Oppa."