At twelve, Li Xingchen, a Chinese orphan, moved to Japan and became close friends with Conan and the others. He consistently ranked first in his school. He doted on Ayumi, Ai Haibara, and his girlfriend, Ran Mori. He had protected Ayumi since she was two, and the two kids were always clamoring for hugs and affection from him.
In their third year of middle school, transfer student Ito Jo, a rich heir, grew jealous of Li Xingchen's popularity. He pretended to be sweet and innocent while spreading rumors and turning people against him. In their second year of high school, Ran Mori, Ai Haibara, Conan, and their other friends were all deceived into cutting ties with Li Xingchen. From his second to third year of high school, Ito Jo repeatedly sent people to hurt Li Xingchen, only to be beaten back each time. His lies also made everyone despise Li Xingchen even more. In their first year of university, the scheming transfer student Jinggang Shangshu grew jealous of Ito Jo's standing in their social circle and went around smearing him.
After his friends turned their backs on him, Li Xingchen returned to China. Two months later, he awakened a farm dimension containing farmland, woods, a bamboo house, and a well whose water held the energy of spirit stones. He stockpiled a vast amount of supplies, and drinking the spirit spring water dramatically transformed his body. He then traveled to a sacred martial arts site to train, and his strength skyrocketed.
Ito Jo and Jinggang Shangshu are both playboys who lust after numerous young women and married women, but are utterly useless themselves. Most of the married men on the island are also in poor physical condition.
A year later, sixty-four people, including Ran Mori, Conan, Ito Jo, Jinggang Shangshu, the Black Organization, and their families, encounter a spatial anomaly and are transported together to a perilous island in another world, where they begin a desperate struggle to survive.
Add a dog, and we'll probably be together again in the end.