Past
Drumming is inspired by a friend's brother, who was a guitarist. It made him admire very much, therefore he started to learn Guitar too, and from there he falls in love with Rock Band. After that, when he went to a music store to buy a guitar, he saw a very beautiful drumset, so he bought the drumset. From then onwards, he started learning drums, this was when he was in middle school second year. Once he fell in love with the drums, he started practicing everyday, until he was satisfied, in the end his arms even got inflammed, and the neighbours started complaining. He could only put wool between the empty parts of the drumset, to reduce the sound of the drums, but luckily his family's encouragement was good.

Three years later, he officially joined the band Zi:kill, at this time, he already knew Hyde who was also at Danger Crue.

His days in Zi:kill
Zi:kill's main members were Tusk, Ken and Seiichi, but they did not have a specific drummer. Yuki is the second drummer, before him was Masami, after him was Tetsu and Eby. The works with him in the band is mini album "Close Dance" (extasy records) and special album "Dearest Town" (toshiba EMI)
After 91's first live, Yuki left Zi:kill.

Music's influence towards school
Yukihiro's results were good from young (especially Math), when he was in Elementary school Fourth grade, he was in track and fields team, is very popular in school and among girls too.
After middle school when he fell in love with drums, his results were still very good, therefore he went into a very good high school with no problems, but once he was in year one, he started growing long hair, and looked like rocker style. The school objected, because this could ruin the school's name, yet even though Yuki was concentrating on music, his results were still very good, therefore the school could do nothing, and this remained throughout his high school life. (hido: way to go yukkichan!)
Later he entered Chibaken's business university, but like Ken, he didn't graduate. Besides the reason of financial difficulties, music also played a very big part. In university, Yuki was famous because his maths and english was good. Besides this, he once became a Maths and English tutor, so people called him "sensei". As to whether his unable to complete university was a pity, it's up to individual to decide.

Optic nerve
It's a band which Yuki and Shin formed outside of Die In Cries, once released album "Optic Nerve Abstraction", Yuki was in charge of drum, percussion, computer programme, remix work. 
The best thing to be noticed is that Yuki sang three songs out of the six, it is the only album which has him as vocal, although it doesn't sound like singing, rather, murmur.

Die In Cries

Independent Development
After leaving Die In Cries, Yukihiro was invited to backstage work, but he once released his own work and conducted a session of solo live.
(hido: below are works which he participated in)

Iijima Naoko; Change My Mind
The Imashigenrei (hido: might be wrong romanization); SION tribute paint nothing you can do
Ken; Who Am I?
yukihiro; yukihiro 8.13 live album
yukihiro; yukihiro 8.13 live video

About live 8.13
this is a live DJ-style, in it, Yuki performs remix and drumming, and rare stances of him singing. That live was also released in album form in Taiwan in May 4 2000, is an album worthy of hearing.

Entering L'Arc~en~Ciel
after there was no Sakura, tetsu was very troubled about the fact that they had no drummer, until one day, he meets good friend Yukihiro on the streets, there was a bit of morning light. The first motive was purely to have Yuki teach him strategies to Eva, but in the discussion he suddenly invited Yuki to help L'Arc~en~Ciel out. 
Therefore, Yuki as a support, played drums in "Niji", at last, all members found that he could be called "L'Arc~en~Ciel's drummer", finally in "L'Arc~en~Ciel 97 Reincarnation"'s live announce that Yukihiro was inside the band. Yuki joined in on the January 1st of 1998.

Yukihiro's vocal
Besides Optic Nerve Abstraction, Yuki has never sung before. L'Arc~en~Ciel's members, however, are interested in his vocal, Tetsu hopes Yuki will sing (Yuki is the only one who isn't involved in background vocals). 
However, Yuki's voice are of the same tone, it sounds like he was tone deaf, but it is not true. While writing "Trick", Yuki didn't use his guitar, but hummed it. When Hyde heard it, he was shocked stiff. As for Tetsu and Ken's views towards his vocal is... Very refreshingly wonderful!
In Grand Cross Tour interview, when asked what they would like to have as a new work, Yuki replied, "Singing", this made the other three laugh out loud.