Taniguchi has brown hair, rather small eyes, and thick lips. He wears a Namimori Middle School team baseball cap and its uniform.
Taniguchi plays on Namimori Middle's baseball team, so it can be assumed that he enjoys playing baseball. He, however, was intimidated by Kaoru's hooligan-like appearance.
Taniguchi was briefly seen during baseball practice asking Yamamoto what he thought of Kaoru. Yamamoto wonders who he is, thinking him to be a graduate student or someone's dad, but Taniguchi reveals him to be a transfer student. When Yamamoto asks Taniguchi why he didn't invite him to practice, Taniguchi defends himself by stating that Kaoru would definitely cause trouble.