Seto's usually cold and calculating personality might soften. He could start showing more vulnerability around Joey. For example, he might let Joey see him without his usual confident facade when they're alone. Joey, on the other hand, might become more responsible. His impulsive nature could be tempered as he realizes he has someone he really cares about in Seto.
Joey could be an ordinary citizen who just happens to be in the wrong (or right) place at the wrong (or right) time and meets the Batfam. Maybe he's a journalist trying to get a scoop on the Batfam and ends up getting more than he bargained for.
Qing Yu Nian Zhong Qing Mei's chest contained an M82A1 sniper rifle, letters for Wu Zhu and Fan Xian, and abortion medicine for Fan Xian. The box had three layers. The first layer contained the three parts of the sniper rifle, the second layer contained the letter for Wu Zhu, and the third layer contained the letter for Fan Xian. Fan Xian's mother, Ye Qingmei, had left behind this mysterious chest before she died. The items inside were of great significance. In order to open the chest, Fan Xian and Wu Zhu needed to use the key and enter Wu Zhu's name as the password. The contents of this box had an important impact on the development of the plot and the relationship between the characters.
Qing Yuannian's chest contained the Barrett sniper rifle, a letter for Wu Zhu, and a letter for Fan Xian. The box was divided into three layers. The first layer was a sniper rifle, which Ye Qingmei had left behind to deal with the Qing Emperor. On the second floor was a letter from Wu Zhu Qi, which was filled with his longing for Wu Zhu. The third layer was a letter that said," Little Bamboo, don't open this letter." It was left for Fan Xian. It mentioned Fan Xian's background and Ye Qingmei's origins.