Soshiro Hoshina

Soshiro is an athletic young man of average height, with a small but muscular build and short dark violet hair cut in a bob style. His purple eyes are closed most of the time and he always has a jovial expression on his face, except when serious situations made him show an imposing expression with his eyes open.

When on duty, Soshiro wears the usual Defense Force uniform. He also wears the normal combat suit worn by Defense Force members when on the battlefield. While using the Number 10 Weapon, Soshiro wears a combat suit with light violet scale-like armor with green outlines, a long mechanical tail, and Kaiju No. 10's signature eye in the middle of his chest plate.

Soshiro is rather laid-back, always having a smile on his face; it is very rare to see him downtrodden. He seems to enjoy making fun of others, especially Kafka Hibino, who considers him comic relief. However, he does have some serious moments when he speaks firmly and widens his eyes to emphasize the seriousness of his words. Soshiro also enjoys making fun of First Division Captain Gen Narumi. Despite Soshiro's laid-back and friendly appearance, he is very intelligent and intuitive. He was the only one who correctly suspected Kafka's identity as Kaiju No. 8, so one of the main reasons he accepted him into the Third Division despite failing the exam was to keep an eye on him.

Soshiro has a strong, albeit hidden, sense of loyalty towards the Defense Force and is very grateful to his captain Mina Ashiro for letting him into her division. His sense of loyalty towards his role in the force is so strong that deep down he sees it as his only reason for living. Soshiro is also very grateful, as seen when he spoke to Kafka two months after he was proven to be Kaiju No. 8 and thanked him for saving his and his subordinates' lives showing that he holds no grudges.

Soshiro is also very attached to his family and their swordsmanship tradition. His father's skepticism of his abilities and his feeling of inferiority towards his older brother Soichiro Hoshina led Soshiro to hone his swordsmanship and identify his entire being within the art of the sword. He was also seen training alone despite it being very late at night, replaying in his mind the fight he had against Kaiju No. 8. This further shows that Soshiro is also very hard-working and is determined to become strong enough to defeat all Kaiju. However, during his fight with Kaiju No. 12, No. 10 delved into Soshiro's psyche and made him realize that he always had fun wielding the sword.

Soshiro is the vice captain of the third division of defense against Kaiju being someone relaxed and funny but at the time of work he is someone serious and in a certain way sadistic.