Tetsuro Segawa

Tetsuro Segawa is a major supporting character in the anime/manga series Guyver: The Bioboosted Armor. He is the older brother of Mizuki Segawa and Sho Fukamachi's best friend. A high school student and science fiction fanatic, he has an easier time than his sister when it comes to accepting the nightmarish reality surrounding the Guyver and Cronos.

Early life
Tetsuro and his sister Mizuki had been friends and neighbours of the Fukamachi family since childhood. He was Sho's senior in high school and was aware of Sho's infatuation with Mizuki before Sho himself was, which he supported. While in high school, Tetsuro ran a science fiction club along with classmate Natsuki Taga.

Before X-Day
One fateful day, Tetsuro and Sho were hanging out after school and walking through the woods near Narisawa Lake. At that time, an explosion occurred on the nearby mountain and a strange piece of debris crashed near them. The two boys investigated and found that the "debris" was a device of some kind, consisting of a metallic core surrounded by seemingly organic coils and held together with metal braces. When Sho touched the device, he inadvertently activated it and it enveloped him. Tetsuro watched in horror and fascination as the strange object seemed to mold around Sho's body who staggered about in blind terror before falling into the lake. Fearing for Sho's life, Tetsuro called out for help, but his cries were answered by a group of strange soldiers that were led by a hulking green monster. As the creature closed in on him, Tetsuro screamed. However, another strange creature suddenly emerged from the lake and fought the beast, killing it in gruesome fashion and prompting the mysterious soldiers to retreat. The creature that had saved Tetsuro then spoke his name and Tetsuro recognised the voice as Sho's. Sho sounded confused by Tetsuro's frightened expression, but then saw his reflection in the lake and was shocked by what he saw. As Sho screamed, the bio-boosted armour separated from him and appeared to vanish into the lake.

After the Guyver's first appearance, Sho remained absent from school and Tetsuro visited him in the afternoon. Sho and Tetsuro discussed what had happened the previous day and Sho revealed two growths on his back that he was certain were related to the object the boys had found. The next day, Tetsuro was taking part in the school sci-fi club and came upon the idea of monsters being created by the military as weapons for a magazine story. He then thought back to the monster he had seen at the lake accompanied by those soldiers, suspecting that a military power really was engineering bio-weapons. He shared his theories with Sho, but the two decided not to investigate into it for their own safety. However, the boys had already caught the attention of Cronos who sent a pair of operatives posing as detectives to capture and question them. The Cronos agents transformed into their Zoanoid forms to scare Tetsuro and Sho into telling them where the lost Guyver unit was, and upon hearing the word 'Guyver' Sho instinctively called out the word and transformed, using his newfound strength and power to defend Tetsuro and kill the Zoanoids.

In the days that followed, Sho and Tetsuro found themselves being hounded by Cronos who sent numerous Zoanoids to try and capture the Guyver. Though Sho fought off these attacks each time, his assailants would also resort to threatening and murdering innocent bystanders which would weigh heavy on the boys' consciences. Even Mizuki would become dragged into the conflict after Cronos abducted her to lure Sho into a trap, and while Sho had managed to save her, she had seen the Zoanoids and Tetsuro could not continue lying to her.

One day, Cronos had called Sho out, threatening to kill everyone he cared about unless he surrendered. Tetsuro accompanied Sho to Mt. Narisawa where a squad of Cronos troopers were waiting, as well as a sickly middle-aged man who claimed to be the former director of Cronos' Japanese branch

UNDER CONSTRUCTION.