Uchi no Deshi ga Itsunomanika Jinrui Saikyou ni Natteite, Nan no Sainou mo Nai Shishou no Ore ga Sore wo Koeru Uchuu Saikyou ni Gonintei sareteiru Ken ni Tsuite

After I was kicked out from my adventurer party, I lived out my retirement in the mountains. However, my disciple became the strongest human in the world without my knowledge, which started the rumor that her master could only be the ultimate strongest person, eclipsing humanity. Hence, I now occupied rank one on the adventurer rankings. An aspiring student, a dragon, a hero, and a demon lord all came flocking to me, completely misunderstanding everything. Please stop. I'm just a small fry, okay? This is not a story about an OP MC. It's a comedy about a bunch of idiots who think I am.

(Source: Shousetsuka ni Narou, translated)