From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Ranran Rōshi (ランラン 老師, Ranran Rōshi) is a martial artist.
Ranran lost in the Elimination Round at the 21st Tenkaichi Tournament. He made it to the final Elimination Round, which would have resulted in him entering the tournament, but he was matched up against Son Goku. He thought that Goku's stance was weird because it left all of his areas open and vulnerable, but he was quickly defeated when Goku threw him out of the ring.
Ranran appeared in Dragon Ball Z: Sūpā Gokū Den: Totsugeki Hen.