He is a member of the Shachihoko Group. He is usually with Chi and Hoko and he is the strongest amongst them. All three of them are from a local Karate club. They like to collect cards by defeating any duelist they found passign by. They all use similar decks and strategy to defeat their opponents.
One day they found Benchan and stopped him and asked to duel them. As Chi had a hunch that he is carrying a collectable cards folder even though he told them that he is not a duelist. Then Katta came in looking for Benchan and saw him in that situation situation. He pretend to be the actual Benchan and challenged them but he lost. Then Benchan came in when they tried to take his cards. Benchan challenged Sha for the duel. Sha used almost same cards and had the same strategy as Chi who earlier dueled and defeated Katta, and from all this Benchan knew when Sha started the same pattern and so he knew how counter it. In the end Sha was defeated by Benchan but then the following day Sha and his friends brought their group leader Onsen who then defeated Benchan.