Masaki Kurusu (来栖征, Kurusu Masaki) is a fictional character in the manga/anime series Getbackers. In the original Japanese version, he's voiced by Hideyuki Hori.
He is the last member of those who were known as the Four Kings during the era of VOLTS. His techniques allow him to control light, bypassing any physical defense and inflicting internal damage, thus earning him the title "the Controller of Light / Flash Master" (閃光の支配者?). He is also able to use light to blind his opponents' senses. Kyoji Kagami refers to him as the "Brain Trust's Masaki Kurusu", so it is safe to assume that he too was a resident of Babylon City and hopes to re-enter his home with the help of the three keys.
In the Manga
The Eternal Bond Arc
Masaki Kurusu makes his first appereance during the 7 Kiryudo Arc. He's watching from the Beltline the battle of his former friends (talking about Shido, Kazuki and Ginji) and also remembering his time when he was a "friend" to Ginji Amano, better known as the Lightning Emperor at that time. Jyouya Kanou arrives, telling him if he misses those time; which he answers that it doesn't matter anymore and that woman has already arrive.
Get Back The Lost Time
to rework & to complete Masaki still watches the GetBackers going through the Infinity Fortress. Kaoru Ujie arrives and tells him that Saizou has captured the members of Fuuga and that Kagami has one of the keys. He remembers his time during the Volts but now it is time to seek their destruction.
Masaki appears again in front of Shido Fuyuki and Kazuki Fuuchouin while they were climbing to the Beltline. They says hi to each other as if nothing had happened and remember they days during the Volts and how all they miss those days but in blank, Masaki activates his stigma and sends thousands of light beams but Kazuki is able to defend them with his coocoon shield. When Kazuki is about to attack for being with the Voodooist, Shido interrupts and tells him he's going to figh Masaki. Masaki sends a light wave and passes through Shido and Kazuki's string and he reveals he never trully joined the volts but just they went on the same direction as his. While Kanou and Kaoru take down Shido, Masaki fires a beam behind Kazuki and knocks him down.
Upon their victory, they return to the Voodoo King which congratulates them for their victory. Masaki states that it was easy because they remembered them as friends. Yohan mocks at his tactis which makes anger Kanou but Masaki tells him to calm down since they are in front of the Voodoo King.
Here, he's a former lover of Hevn, a good friend of the GetBackers duo. He tried to forget his love, and attempted to kill her. But, in the end, the lovers embraced after Masaki's fight with Ginji Amano. Masaki is also one of the bearers of the 'Stigma'. In fact, it was he who taught a young Kazuki how to suppress the power of the 'Stigma'. He is the one who reveals to the reader the origins of the Brain Trust.
In the Anime
Here, his alliance with Babylon City is stated openly; he kidnaps MakubeX on their orders and reveals that he had been spying on Raitei and Volts for Brain Trust while he was one of the Four Kings, despite having been a close friend of Takeru Teshimine, who found and raised Ginji in Infinity Fortress as a child. During his alliance with the Volts, however, he found happiness and when the Brain Trust decided to delete MakubeX, Masaki saved him.
He does not create light. The light is generated from light. To put it simply, if Masaki and Character B are standing about four to five car lengths away from each other, he can manipulate the light particles in the environment to attack Character B basically as fast as light can move. That's what Masaki can do. He doesn't create light, he manipulates light from light particles within the environment. By that, he can create knives, swords, and etc with light particles. Everything is in light, so he can manipulate the light. He can blend in with the light to reflect off of other light particles for light speed attacks.Masaki has the ability to manipulate and command light.
Masaki has the ability to become an entity of pure light. This basically allows him to bypass any defense as well as allow any other attack to pass right through him. His techniques allow him to control light, bypassing any physical defense and inflicting internal damage. Not even solid substances can escape his light. He is able to use light to blind; command all of his opponents' senses.
By blending in with the light and the surroundings, Masaki is able to manipulate light particles to cloud the environment and conceal his presence completely. Masaki is able to move instantly anywhere within light making it very hard to fight him. Masaki is able to command light to block him from attacks or use light particles within the environment to attack. Masaki can manipulate light particles to create many forms of objects. Some include swords, mirrors, and even scalpels like Dr. Jackals.
Masaki bears thi Stigma, he is granted with immense power. All of his natural abilities and stats are augmented to their absolute best. Through the power of his Stigma, he can pass through dimensional barriers easily. It allows him to attack intangibles, noncoporeal beings, and coporeal beings in his situation. The Stigma also greatly increases the power of its user's will; or better yet reality manipulation. It is a curse, but a gift at the same time. Through the use of this power, he is also able to affect time and space and the universe itself.