|Name in Japanese||タチバナ・カズキ|
|Rōmaji Translation||Tachibana Kazuki|
|Debut (Anime)||Episode 01|
|Voice Actor (Japanese)||Tetsuya Kakihara|
|Voice Actor (English)||Todd Haberkorn|
|Affiliation||ISDA, Lindworm Unit|
Kazuki Tachibana (タチバナ・カズキTachibana Kazuki?) was Jin's best friend from before the accident. The two had promised to go into space together, resulting in their admission into the astronaut training program, but the shuttle accident caused Jin to leave the program.
Kazuki now works for the ISDA as part of the Dragonauts after his successful Resonance with Gio. In order to fulfill their promise, he tries to get Jin to join, ignorant of Jin's trauma of the shuttle accident.
However, after seeing Jin fly off with Gio, he starts to feel some anger and resentment towards Jin. He partners up with another Communicator named Widow, who lost her original partner, in order to retrieve Gio himself. He eventually cuts his hair to a more wild and crazed look to reflect his rage. He constantly acts rashly and violently in his attempts to retrieve Gio, whom he considers to be an object that belongs to him. Later, during a battle with Jin and Gio, he receives a scar between his eyes.
After the ISDA falls under Gillard command, he remains with them, and works with Widow in order to capture other dragons. However, after Widow's death, he comes to realize his true feelings, and reconciles with Jin after a brief altercation.
In the manga, he is introduced as a Dragonaut, whose dragon partner is Gio.
|e v||Lindworm Unit|
|Members:||Raina Cromwell | Howlingstar | Akira Soya | Machina | Sieglinde Baumgard | Amadeus | Kazuki Tachibana | Keiichi Amagi | Spirytus ||