Dragon Ball: I Am Tarble

[No System + Hard Work + One Heroine + Super Saiyan 4 Route]

A soul from Blue Star transmigrates into the body of Tarble, Vegeta’s supposedly useless younger brother. He has never watched Dragon Ball and has no System. Every bit of his combat power comes from opportunities and his own hard work, built up through training one step at a time.

Here, he and Vegeta become true brothers who would risk their lives for each other, and he forms deep friendships with Son Goku, Krillin, Tien Shinhan, and the others.

The protagonist is headed down the Super Saiyan transformation route,

while Son Goku and Vegeta take the Super Saiyan God route.