Klaus

Klaus is one of the strongest brawlers

Relationships
Shun: Before Maquerade beaten everyone. Shun and Klaus were the 2 strongest brawlers.

since due to that. Klaus and Shun were good friends.

Stoica: Stoica and Klaus became best friends after Stoica defeated Klaus cause Klaus said he was a great opoment.

Battles
Klaus is the 2nd strongest aquos brawler in the anime due to losing against Stoica