It may be the lychee stem borer. This insect is mainly distributed in lychee and longan producing areas in Guangxi, Guangdong, Fujian, Taiwan and other small areas. Its larvae damage the main veins and flowers of the young leaves behind lychees and longans. During the expansion stage of young fruits, the fruit core is damaged by the borer. After the fruit develops, the fruit pedicle is damaged, causing the midrib of the young leaves to turn brown, the epidermis to break, and the top of the flower spike to die, affecting fruit quality and yield.

These bugs only harm plants and will be fine if eaten in the stomachs of humans and other animals. But it's just a little disgusting.