Mint is a girl who lives in the village at the foot of Popo Poco Volcano. Krillin, Yamcha, Tien Shinhan and Chiaotzu met her and her brother Paul while they were going to Korin Tower three years before the 23rd World Martial Arts Tournament.

While Krillin, Yamcha, Tien Shinhan and Chiaotzu were going to the Korin Tower, they are ambushed by people in devil masks. Among them, Mint invites the boys to their festival. There, a stranger gives Krillin alcohol and he quickly gets drunk. Tien is challenged by Paul, Mint's brother. However, Krillin wants to fight the man first to impress the girl and defeats him with a headbutt.

When Popo Poco Volcano erupts, the boys go to the volcano to change the course of the lava. The elder of the village refuses to leave, and Mint and her brother cannot make him move. Krillin runs to save Mint from the lava flow, but still, she will not leave without the elder. Krillin then tries to block the village with a big rock. Yamcha blasts a hole for water to flow though and manages to flood the entire forest, but somehow, not the village. Everything is fine until the volcano erupts again. Together, Yamcha and Tien blast a rock wall that diverts the lava and protects Mint's village.

(Source: Dragon Ball Wiki)