C33 Another Study in the Dark Room

Gu Xiaoyu was sitting next to Gu Xiaoxi, so he didn't notice that Zhou Chengan had dug out the small wooden box. However, there was a strange lock on the wooden box. The surface of the lock was caved in, an irregular pattern. He felt as if he had seen it somewhere before, but could not recall where it came from.

"Miss Gu …" Zhou Cheng'an walked to the front of Gu Xiaoyu and squatted down