Yu Han Sung

"It's really quite simple. All you have to do is walk off this stage with your mind intact." - Yu to Mauchi

Yu Han Sung is a Ranker and the test director of the Second Floor, and appears to be an antagonist in the first part of the series. He also seems to dislike the Zahard family.

Appearance and Personality
Yu Han Sung is a human man with long blonde hair. One odd thing about him is that he looks like a woman. He always wears robes, usually blue and yellow.

He is quite intelligent and perceptive. He is also addicted to coffee, which is the cause of many jokes directed at him. Behind this simple outer shell however, is the fierce and deadly "Submerged Fish" who destroys those who may be dangerous to The Tower. Yu subtly hides the fact he is extremely haughty, although to some extent, this is reasonable, considering his power. Yu considers himself to be a "filter" for the tower, and so thinks himself cunning, manipulative, and powerful. He admits that he is shaken by princesses and stronger high-rankers, though he can still keep his cool regarding his strength, position and status.



Plot Summary
Yu Han Sung is one of the Rankers proctoring the tests on the Second Floor. He directly proctors the Door Test, in which the Regulars have to rely on a few scant clues to select the "correct" door out of twelve identical doors. The real answer to the test was in fact to open any door before five minutes were up.

Later, Yu observes the hide-and-seek test with Lero-Ro. He is in charge of grading the overall team. He talks to Lero-ro about Koon's performance, cryptically noting that Regulars would have to drop off "excess weight", signifying their comrades, as they climbed higher and higher up the Tower. He also reveals his cruel side, as he states that he wanted to destroy Koon due to his multi-faceted personality.

When he announces the results of the Position Test, Mauchi becomes angry; Yu snaps his bones with Shinsoo. Koon then comes down and says that he wishes to get a test from the Guardian, to which Yu replies that he is insane and that to get such a test one would need to be an Irregular. When Baam reveals that he is an Irregular, Yu allows him to see the Guardian. Afterwards, he tells Baam that he has been trying to destroy him all along.

Before the Final Test, he tracks down Ren and engaged him briefly, before stating that their goals were the same and that there was no reason for them to fight. He reveals his power to Ren as the "Submerged Fish" of the Second Floor.

During the Final Test, he reveals to Evan that everything had been planned by the Guardian, and that the seemingly unusual events were part of the test. He also seems to have some connection with Rachel and Head-On.

Powers and Abilities
Yu Han Sung is a powerful ranker and apparently a genius Wave Controller. An example of his strength is his ability to easily summon and control an enormous fish close to the size of a White Steel Eel. It can be considered that he was an incredibly powerful genius when he climbed the tower; Ren stated that Yu possessed power that even shocked the Vice Commander. He is at the standard of a High-Ranker's strength. It is funny to note that when Yu said he didn't want to fight Ren, it wasn't Yu being afraid of Ren's power, but more the political consequences of a battle against a RED member. Proof behind this is the fact that mathematically, Yu is 1.6 times Ren's strength.