- "The days ahead will be full of long and arduous training."
- ―Sun to Ryo
Master Sun (Hànzì: 孫九思, Pinyin: Sūn Jiǔsī, On'yomi: Son Kunshi) is an old homeless who resides in Bailu Village. By the time Ryo reaches Bailu, Sun has moved to the Abandoned Temple of the village. Despite his ragged appearance and his love for alcohol, he's a skilled martial artist, who used to study with grandmaster Feng when the two were young. Now they're still good friends. Sun is also one of the eldest members of the village, alongside Xiuyu Yeh and Wenxu Su.