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!
—Yudai Moroboshi
Yudai Moroboshi
Yudai profile pic
Kana 諸星雄大
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 Koume Moroboshi (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

Yudai Moroboshi is a student from Bukyoku Academy and the previous winner of the Seven Stars Sword Art Festival. Like the year before, Yudai participates as one of the three representatives of his school in the Festival.


Yudai is a handsome young man with blonde hair and green eyes. He is usually seen in his school uniform and wears a hachimaki.


Yudai is a cheerful, talkative, straightforward young man. Yudai 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, Yudai 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, Yudai is seen as a home town hero and is very well 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, Yudai grew quite famous, participating inJapan's Little League. During his primary school period, Yudai was involved in a severe accident that almost left him crippled and had to retire as a Knight for 4 years. This leads to Yudai's sister Koume Moroboshi, blaming herself for what happened to Yudai, which resulted to her being traumatized to the point she was unable to speak. Because of this, Yudai underwent rehabilitation with the help of Kiriko Yakushi. After hard work, Yudai finally got better and even won the 61st Seven Stars Sword Art Festival against Byakuya Jougasaki. He also challenged and beat opponents such as Tohka Todo in the semi-finals of the Festival. After his victory, Yudai 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 Edit

Party Crashers Edit

Yudai 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 Yudai never proceeds as other representatives come into the confrontation causing Yui to leave in shame. Yudai then introduces himself to Ikki, his first opponent in the Seven Stars Sword Art Festival.

Dinner and Confrontation Edit

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

After Ikki and company had left, Ikki gets attacked by Ouma, with Yudai eventually coming to help him. Yudai 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 Yudai takes a heavily injured Ikki to the hospital.

Battle of Kings Edit

LN Volume 5 color illustration 4 Yudai stands before Ikki with a fearless grin

Yudai vs. Ikki.

Yudai, 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 Yudai as Ikki takes heavy damage by the combination of Sanrensei, Houkiboshi and his Noble Art Tiger Bite which nearly destroyed Ikki's device.

Yudai, 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 Yudai's spear, however Ikki was unable to land the final blow allowing Yudai to hit Ikki with the back of the hilt of Yudai's spear.

Yudai 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. Yudai is then quickly overpowered by Ikki and his new sword technique.

LN Volume 5 illustration 11 Koume finally cheers for her brother

Koume encouraging Yudai.

Yudai 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. Yudai 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 Yudai would never give up, he could see through this trick and used his after image sword technique to trick Yudai and then slash to finally put down the Sword King once and for all, giving Ikki the win. Yudai is then carried off on a stretcher after giving Ikki some encouraging words.

Conclusion of the First Match Edit

Yudai 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 Yudai probably wants some time on his own after his loss.

Yudai 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.

Rising Spirit Edit

Yudai and many other students help Ikki train for the upcoming finals of the Festival, where he will face Stella Vermillion. Yudai 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, Yudai puts up a good fight, initially having the advantage due to his faster Sanrensei. Ikki, however, defeats Yudai by minimizing unnecessary movement and cut off any unnecessary senses, adjusting to Yudai's attacks and defeating him.

Yudai is later seen watching the finals of the Festival, between Ikki and Stella, which Ikki wins, becoming the new Seven Stars Sword King.

LN Vol 10 Illustration 2

Tohka and Yudai

Vermillion Empire Arc Edit

The Festival Is Over Edit

After the Festival Yudai is seen talking with Tohka Todo, about their futures, and how he is thinking about going to China, to fight in the God of War League. They are shown having a rather close relationship.


Master Spearmanship: Yudai's main form of combat next to his Noble Arts. His well-honed skills with his Device allowed him to defeat dangerous opponents such as Tohka Todo. This feat made more impressive because he was able to keep himself out of Tohka's Raikiri range throughout the match. The sheer power, speed, accuracy, and skills he possesses has caused even a well-rounded martial artist of Ikki Kurogane's level to be greatly impressed many times during their first match.

  • Happo Nirami (八方睨み, lit. "Glare in All Directions"): A defensive stance that Yudai employs. It is praised as being without openings from all directions by Ikki.
  • Sanrensei (三連星, lit. "Three Linked Stars"): Yudai's high-speed spear technique which involved striking three points at once. The technique's speed is lowered when Yudai uses Houkiboshi or Tiger Bite with it. At its absolute speed, Ikki mentioned it being like a meteor shower.
  • Houkiboshi (帚星, lit. "Comet"): A homing-thrust technique which involves the movement of the wrist. Yudai 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 the technique can be extremely difficult and blocking it is also made dangerous due to Yudai's ability to destroy a Device of a Blazer.

Immense Speed: Yudai 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: After having made it through his hell like rehabilitation, Yudai has gain incredible amounts of physical and mental endurance.

Keen Intellect: Yudai is well-known for his cunningness in battle, capable of misleading his opponent's into a false sense of confidence under multiple layers of traps to defeat them. He can also figure out the weaknesses in a person fighting style and make plans on how to best deal with them. He was able to see through Ikki's intention when using Dokuga no Tachi and make a trap of his own to counter the technique, although he had never seen that technique before. Yudai also has shown being able to adapt and improve his tactical skills, being capable of seeing through Ikki's Shinkirou after seeing it once.

Magic Destruction: Yudai's Blazer ability allows him to destroy other Blazers' magical abilities. He can easily break through both Device and Noble Art of even an A-Rank Mage-Knight. This gives him an advantage against Mage-Knights who mainly fight using their Blazer abilities, although the ability is less useful against Blazers who utilize mainly martial arts.

Yudai's Device

Yudai's Device


Tora-Ou (虎王 literally, "Tiger King"): Yudai's Device. It takes the form of a yellow spear.

  • Tiger Bite (暴喰タイガーバイト, Taigā Baito): Yudai's trademark Noble Art, it creates a Golden Tiger made from magic power and can devour almost anything in its path. Also due to its properties of being made from magic power, the Golden Tiger can devour the opponent's Device and Noble Art to power up but the tiger is unable to cause physical damage in return.


  • Yudai's techniques and nicknames are themed around stars. Even the kanji for "boshi" (星) means star.