Rakudai Kishi no Eiyuutan Wiki
You didn't claw your way up here just to get into this sort of petty quarrel, did you?
—Yuudai meeting Ikki for the first time
Yuudai Moroboshi
Yudai profile pic.png
Kana 諸星 雄大もろぼし ゆうだい
Romaji Moroboshi Yūdai
Gender Male
Age 17
Nickname/s Star of Naniwa
Seven Star Sword King (formerly)
Hair Color Blonde
Eye Color Green
Device Tora-Ou
Personal Status
Relatives Unnamed Mother
Unnamed Father Koume Moroboshi (Younger Sister)
Affiliations Bukyoku Academy
Ichiban Boshi
Status Active
Blazer Status
Ranking B-Rank
Physical A
Luck E
Offense C
Defense A
Magic Cap C
Magic Ctl C
Voice Actor

Yuudai Moroboshi is a third-year student in Bukyoku Academy and the previous winner of the Seven Stars Sword Art Festival known as the Star of Naniwa. A lot like the previous year, he participated as one of the three representatives of his school in the current festival.


Yuudai is a handsome young man who has short spiky blonde hair and green eyes. He also has a lean and muscular build due to all of his extensive rehabilitation training. Most of the time, Yuudai is seen dressed in his Bukyoku Academy, consisting of a black jacket with a series of golden trims with a gold strap linked on his shoulder, black pants, hachimaki, a black shoulder cape during his first appearance before the initial of the 62nd Seven Stars Sword Art Festival, and he wears black gloves from time to time.


Good food is good motivation, y'know? So just take the day to rest up, and then meet me in the match tomorrow in your best condition, better than you've ever been. Provin' my strength by defeating an opponent at their strongest—now that's well worth the meal I treated!
—Yuudai Moroboshi

Yuudai is a cheerful, talkative, straightforward young man. He is modest enough to not underestimate others and doesn't feel he should be called the Seven Star Sword King because the A-Rank Ouma Kurogane didn't participate in the previous Seven Stars Sword Art Festival.

Like Ikki Kurogane, Yuudai is very strong-willed and hard-working when it comes to whatever goals he sets for himself and doesn't give up until he reaches them, no matter how hard it is. This was proven by the fact he was able to make it through his hell-like rehabilitation and go on to become the Seven Star Sword King. Because of these traits, Yuudai is seen as a home town hero and is very respected by almost everyone who knows him personally. He also seems to be very tactical in battle as he came up with very clever ways to try and combat Ikki's movements even in his most dire of situations.


Even during his childhood, Yuudai grew quite famous, participating in Japan's Little League. In his primary school period, Yuudai was involved in a severe accident that almost left him crippled and had to retire as a Knight for four years. This leads to Yuudai's sister Koume Moroboshi, blaming herself for what happened to Yuudai, which resulted in her being traumatized to the point she was unable to speak. Because of this, he underwent rehabilitation with the help of Kiriko Yakushi. After hard work, Yuudai finally got better and even won the 61st Seven Stars Sword Art Festival against Byakuya Jougasaki. He also challenged and beat opponents such as Touka Toudou in the semi-finals of the Festival. After his victory, Yuudai was considered to be part of the Golden Generation, the three strongest students of Bukyoku Academy, also including Byakuya Jougasaki and Momiji Asagi.


Seven Stars Sword Art Festival Arc

Party Crashers

Yuudai is seen defending Ikki and confronting Yui Tatara, who had tried to severely injure Ikki's sister with sharp metal blades in the meat Shizuku was about to eat. The battle between Yui and Yuudai never proceeds as other representatives come into the confrontation causing Yui to leave in shame. Yuudai then introduces himself to Ikki, his first opponent in the Seven Stars Sword Art Festival.

Dinner and Confrontation

Yuudai meets Ikki, Shizuku, and Nagi and invites them to his family restaurant, Ichiban Boshi, to which they accept. During their time at the restaurant, Yuudai is unable to join them as he is busy helping the family with the restaurant.

After Ikki and co left, Ikki gets attacked by Ouma, with Yuudai eventually coming to help him. Yuudai is seen stopping Ouma's Kusanagi attack on Ikki, by using his Tiger Bite to completely stop Ouma's powerful attack. Ouma then decides to leave and Yuudai takes a heavily injured Ikki to the hospital.

Battle of Kings

Yuudai vs. Ikki.

Yuudai, the next day, confronts his opponent Ikki at the Seven Stars Sword Art Festival. The fight begins and Ikki tries to get the upper hand but is badly outmaneuvered and outwitted by Yuudai as Ikki takes heavy damage by the combination of Sanrensei, Houkiboshi, and his Noble Art Tiger Bite which nearly destroyed Ikki's device.

Yuudai, however, was nearly beaten by Ikki who was able to use his fourth secret sword technique to create an after image, causing him to be able to get passed Yuudai's spear, however, Ikki was unable to land the final blow allowing Yuudai to hit Ikki with the back of the hilt of Yuudai's spear.

Yuudai then tries to finish off Ikki but senses something dangerous within Ikki, this is proven right as Ikki finally realizes that his subconscious was trying to use Edelweiss' technique all along, which he picked up using Blade Steal in their last meeting. Yuudai is then quickly overpowered by Ikki and his new sword technique.

Koume cheers on Yuudai.

Yuudai is then seen badly cut up by Ikki's barrage of attacks that he could not possibly keep up with, causing his sister Koume, who was in the stands, to finally call out to him and cheer him on.

Yuudai then shows his final hand and tries to mess Ikki up by throwing his spear at him knowing he would not be able to dodge as Edelweiss' technique's one major flaw was that if taken by surprise the user could not stop to dodge. However because Ikki believed that Yuudai would never give up, he could see through this trick and used his after image sword technique to trick Yuudai and then slash to finally put down the Sword King once and for all, giving Ikki the win. Yuudai is then carried off on a stretcher after giving Ikki some encouraging words.

Conclusion of the First Match

Yuudai later meets Ikki and Nagi in the bathhouse, where he orders Byakuya Jougasaki to stop teasing Ikki. Ikki and Nagi then leave, as they think Yuudai probably wants some time on his own after his loss.

Yuudai later is seen speaking to Byakuya, before the latter's match against Ikki. Byakuya proclaims that Ikki won't use his Ittou Shura or Ittou Rasetsu, as he will need them for his third match on the same day. Because of this Byakuya believes he will defeat Ikki in 23 moves. Byakuya is proven wrong though as Ikki uses Ittou Rasetsu, and wins in 0.8 seconds.

Tournament Final

Yuudai and many other students help Ikki train for the upcoming finals of the Festival, where he will face Stella Vermillion. Yuudai has a mock battle with Ikki, not using Tiger Bite due to not wanting to damage Ikki's Device, which would tamper with the upcoming finals. Despite this, Yuudai puts up a good fight, initially having the advantage due to his faster Sanrensei. Ikki, however, defeats Yuudai by minimizing unnecessary movement and cut off any unnecessary senses, adjusting to Yuudai's attacks and defeating him.

Yuudai is later seen watching the finals of the Festival, between Ikki and Stella, which Ikki wins, becoming the new Seven Stars Sword King. He later attends the awards ceremony.

Vermillion Empire Arc

The Festival Is Over

Tohka and Yuudai

After the Festival Yuudai is seen talking with Touka Toudou, about their futures, and how he is thinking about going to China, to fight in the God of War League. They later promise to have a rematch in the KOK A-League someday.

Unnamed Arc

"Sword Eater" vs "Star of Naniwa"

Yuudai arrives in the training facility where everyone else was located where he soon revealed that he was planning on entering the God of War League and wanted to talk with Nangou Torajirou who had entered the same tournament, but found out that he had left to search for Bakuga Tsukikage who has been out of contact. Not wanting his trip to Tokyo to go to waste, he instead approached Kuraudo Kurashiki who was in the same location and challenged him to a fight.

Blessed Power

Chain of Fate


Magic Destruction: Yuudai's ability as a Blazer. He is able to negate the magic of other Blazers, thus making him a threat to the Devices and Noble Arts of even an A-Rank Blazer, especially those who rely on their magic.

Immense Strength: Having undergone a hellish rehabilitation in order to regain the muscles in his upper body in primary school, which was meant for first-rate athletes. As such, it granted him an exceptional physical condition that granted him an A in Physical Attributes.

Immense Speed: Yuudai can move and strike at such amazing speeds that most people watching him fight can't even see most of his actions. His strikes are even able to temporarily corner Ikki, who used Edelweiss' technique to improve his speed.

Immense Stamina: Having made it through his hell-like rehabilitation, he has gain incredible amounts of physical and mental endurance. In his match against Ikki, he was able to get up after briefly losing consciousness from the latter's attack and could endure his high-speed slashes without giving up.

Master Spearmanship: Yuudai is an incredible master spearman who has honed his skills to where Muroto said it was his most dangerous trait. He was able to defeat opponents such as Raikiri and the Clairvoyant, both skilled Student Knights, the latter never won against him. His power, speed, precision, and skills were enough to make a well-rounded swordsman and martial artist such as Ikki to become impressed several times in their first match.

  • Happo Nirami (八方睨み(はっぽう・にらみ) Happō Nirami, lit. "Glare in All Directions"): A defensive stance that Yuudai uses, which is praised as being without openings from all directions by Ikki.
  • Sanrensei (三連星(さんれんせい) Sanrensei, lit. "Three Linked Stars"): His high-speed spear technique which involved striking three points at once. The technique's speed is lowered when Yuudai uses Houkiboshi or Tiger Bite with it. At its absolute speed, Ikki mentioned it being like a meteor shower and even with Edelweiss speed of moving has barely able to dodge.
  • Houkiboshi (ほうき星(ほうきぼし) Hōkiboshi, lit. "Comet"): This is a homing technique, which involves the movement of the wrist. He uses this technique by tricking his opponent into stepping into his range by using on thrust in his move and traps them with Houkiboshi. Avoiding this technique can be extremely difficult and blocking it is also made dangerous due to Yuudai's ability to destroy a Device of a Blazer.
  • Blind Spot Thrust: A unique thrust, which attacks through the opponent's blind spot so that it is invisible to the opponent.

Keen Intellect: Yuudai is well-known for his cunningness in a battle similar to Ikki, able to mislead his opponents in false confidence, setting up multiple traps to defeat them. He can figure out the weaknesses in a person's fighting style and make plans on defeating them. He was able to see through Ikki's intention when using Dokuga no Tachi and make a trap of his own to counter it, although he had never seen it before. Yuudai also has shown being able to adapt and improve his tactical skills, being capable of seeing through Ikki's Shinkirou after seeing it once.

Killer Instinct: As a result of the incident he had experienced, he became able to sense death, letting him sense things others cannot. Yuudai used this a number of times to locate a surefire weakness in his opponent, which is why someone such as the Clairvoyant was afraid of him. The most notable being when he located where the soul of Tendou was and used Musou Ichiretsu to kill him.

Willpower: Yuudai also has incredible willpower and spirit, being able to undergo the hellish rehab despite being a child in his sixth-year, which even Muroto, a professional Blazer who participated in the KOK A-League couldn't even endure after just three days and broke down into tears.


Yuudai's Device

Tora-Ou (虎王, Tiger King): Yuudai's Device, which takes the form of a yellow spear. It is possible for him to break down the magic inside his Tora-Ou, thus causing his spear to take form as a javelin, which he hurled at Ikki in a last-ditch effort to win.

  • Tiger Bite (暴喰(タイガー・バイト) Taigā Baito, lit. "Cruel Devouring"): His trademark and renown Noble Art, where his Tora-Ou shines with a gold light from his magic taking form as a tiger head able to devour his opponents' Device and Noble Arts, however, it is unable to cause physical damage. Tiger Bite was powerful enough to negate Kusanagi, which defeated both Tohka and Stella. Yuudai has later proven to be able to "Enchant" his Tiger Bite onto the Device of another Blazer granting it its power, however, this destroys their magic.
  • Musou Ichiretsu (無双一烈(むそう・ いちれつ) Musō Ichiretsu, lit. "Unparalleled Single Ferocity"): This is the second Noble Art of Yuudai, where he stab his opponent using Tora-Ou in their chest, destroying the source of their magic with Tiger Bite, as such it destroys their body and soul at the same time.


  • His first name (雄大) means "Majestic".
    • His surname (諸星) means "Various Stars".
  • Yuudai's techniques and nicknames are themed around stars. Even the kanji for "boshi" (星) means star.
  • Yuudai is the second person after Kaito Ayatsuji who lost to Kuraudo Kurashiki at the last moment due to his Marginal Counter while leaving him wondering what would occur if their last technique landed.
  • Yuudai is the first Blazer to defeat a Desperado without being one himself, however, the same person returned as a spiritual being.