Lero-Ro serves as the Light Bearer position instructor and Examiner of the Second Floor. He's genuinely old—older than even Yuri Zahard, which is saying something. The two actually go way back; they were both Regulars climbing together at one point.
He and Quant have this weird dynamic that Yu Han Sung apparently labeled a "Set Menu," though the exact meaning of that is unclear. Lero-Ro's well-known enough that his profile shows up on the network Light Bearers use, so he's got some real reputation in those circles.
The climb took him over 300 years, which gives you a sense of how serious Tower climbing is, even for someone who eventually became an instructor.
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