Jadeite

Jadeite was the first of the four Shitennou from the Dark Kingdom. It is later revealed that he was a general of Prince Endymion.

Appearance
Jadeite has very short, closely cropped hair, and is the only member of the Shitennou who can boast this trait. It is colored as a very pale blonde and is parted off to the right-hand side of his head. His eye color is grey. Outside of his disguises, he is typically seen wearing his Shitennou uniform. His accent color is red.

Pretty Soldier Sailor Moon
Jadeite is the first of the Dark Kingdom's Shitennou to appear in the manga, debuting in Act 1 but remaining unnamed until Act 2, when he calls himself the commander of the Far East.

His first plot is to have a youma pose as Naru Osaka's mother at the Jewellery OSA-P store selling jewellery which drains its wearers of their energy. When this first plot fails, he moves on to his second plot, where he sets up a cram school attended by Ami Mizuno called Crystal Seminar, where students are drained of their energy.

After this, too, fails, his final plot, in Act 3, is to trap the senshi on a bus. He kidnaps students riding the 6:00 bus from Sendai Hill, which is near the Hikawa Shrine. He manages to hypnotize Rei Hino boarding the bus, and takes the bus to another dimension. Sailor Moon and Sailor Mercury confront him, Sailor Moon uses her Moon Tiara Boomerang to prevent him from moving. He can still, however, use powers stemming from his vision, and attacked both Senshi. Sailor Mercury prompted Luna to throw the transformation pen towards Rei, where she transformed immediately and became Sailor Mars and attacks him with her exorcism scrolls, in which Jadeite was killed.

His skeleton was preserved in a glass coffin and Nephrite vows to bring him back to life, which Jadeite temporarily does when Princess Serenity is awakened. Unfortunately, he and the other Shitennou were immediately turned into their namesake stones afterwards.

In the later side story Casablanca Memories, Zoisite also tried and failed to avenge Jadeite's death.

Later, when the Silver Crystal appeared, it was revealed that during the Silver Millennium, Jadeite and the other Shitennou originally were not evil - they served under Prince Endymion as his guardians and advisers. They were, however, tempted by the power of the Dark Kingdom (like most other humans), and fell to it. They eventually become good again, and their spirits advise Mamoru when he needs their help.

Pretty Soldier Sailor Stellar
Jadeite makes his first and only appearance in Act 7 when he, along with the rest of the Shitennou, are called upon by Mamoru for spiritual guidance. They reassure him of his strength and power, and urge him to continue on protecting Princess Serenity.

Trivia

 * His name is derived from the mineral Jadeite.
 * In a picture featuring the Sailor Senshi and the Shitennou, Jadeite is paired up with Sailor Mars. In Act 3, Jadeite even noted that Rei (before she became Sailor Mars) was beautiful, and had been attracted to her since the moment he first saw her.