Nasuti aids the Troopers during their quest against the forces of evil. Not much is known about her past, except that she is half French and half Japanese, and was visiting her grandfather when Talpa's invasion began. Unlike her friends, Nasuti has no super powers or weapons. However, she is extremely knowledgeable about the mystical armors and various ancient artifacts. She provides vital information to the Troopers and acts as a caretaker for Ully. Over time, Nasuti becomes like an older sister to them.  In the beginning of the TV series, Nasuti is 17 years old. In Gaiden, she is 19 years old. During Kikoutei Densetsu (The Legend of the Inferno Armor) and Message she is in her early 20s. During Kikoutei Densetsu, Nasuti was crucial in aiding the Troopers in decoding the mysterious language used by Mukara; and she was able to take herself and her friends to where Ryo and Sage were located.  In the 3rd and last OVA, Message, Nasuti was in New York City, where she was attending a special session of the United Nations General Assembly that was convened by the United Nations Security Council to solve the recent, bizarre events that have been happening worldwide; which was seen as a threat to international peace and security. During the meeting, Nasuti planned on telling the world officials about the existence of the Troopers. Whether she succeeded in doing so remains a mystery. Unlike the previous episodes, Nasuti only appears in the very last episode; but as always she provides support for Ryo who, at the time, was about to confront the new enemy, Suzunagi. Nasuti's birthday technically falls on two dates, due to an error made by her creators at Sunrise Animation Studio. According to the YST book, Memorials, her birthday is listed on May 15, 1970, making her a Taurus. However, according to many other official YST merchandise, her birthday is listed as May 28, 1970, thus making her a Gemini like Seiji. Both official books were compiled by Sunrise; however, the latter date is often used in other official documents. It is also the most popular birthday used by fans.  Nasuti's family name, Yagyū is based on the real Japanese clan with the same name. Like most of the characters in the series, many of their surnames are based on historical Japanese clans. Nasuti plays the same role in the manga as she does in the anime version of YST. She provides assistance to the heroes but unlike the anime, her importance is downplayed in order to make room for more action. Jun, the little boy who counted on the Troopers and Byakuen (White Blaze) to protect him, becomes more of a key figure.

Thousands of years ago, the evil emperor Talpa attempted to conquer the Earth. Defeated, he was banished to the Nether Realm and his armor was divided into 9 separate suits. Now, he has returned to conquer Earth, having reclaimed 4 of the suits. The other 5 are in the possesion of those who are the only hope of stopping him: The Ronin Warriors. 
(Source: Anime News Network)

Lalainia Lindbjerg is a Canadian voice actress who works for Ocean Studios in Vancouver, British Columbia, Canada. She has played several roles in anime, known for her role as Bulma. She is married to Brad Strelau and has a son, Caedence Strelau and a daughter, Aurielle Strelau.  Before she was credited as the English voice of Stella Loussier in Gundam SEED Destiny, Kelly Sheridan had mistakenly received the credit for Stella's English voice according to most anime web sites before SEED Destiny was released in North America.  In her theatre credits her last name is hyphenated and is credited as Lalainia Lindbjerg-Strelau.  (source: Wikipedia)

Things have calmed down considerably since the defeat of Talpa.​ Sage has gone off to America to study; Ryou is celebrating his birthday; Kento's won the lottery! However,​ the joyous mood disappears when the local news breaks a story about a strange killer in New York wearing mysterious armor.​ When the four warriors arrive to investigate,​ they are met by a new sinister force.​ The ancient sorcerer Shikaisen has discovered the power of the armors and is now intent on making them his own. 
 
(Source: Bandai Entertainment)

A strange, silent warrior appears. When the Inferno armor is summoned to battle him, the mysterious warrior calls forth his own armor &ndash;a black copy of the Inferno armor! Now, the warriors will find themselves half a world away fighting once more to save humanity, but this time, from their own armor! 
(Source: AniDB)

The Samurai Troopers are five warriors who were given magic armor and must use it to defeat Arago and his warlords.

Nasuti Yagyuu