Ocuppation Platoon Leader in the First Division of the Defense Force Tachibana seems to be a quite serious individual, despite being oftenly surprised in the battle field. He also seems to get irritated quite easily.

Spoiler

Ever since joining the First Division, Tachibana trained and witnessed her countless attempts to become stronger and more beautiful in order to impress Captain Gen Narumi. At some point, Tachibana was promoted to Platoon Leader.