My Mister Ostrich - Chapter 52 Indissoluble Interest

Finding himself in an Last Airbender without an airbender around, a transmigrator waterbender goes on an adventure to stop the worst from happening to him.

An ordinary (?) grandfather, Choi Chuntaek. In an effort to protect his granddaughter, he started the virtual reality game 'Arkstar.'

Then... he accidentally obtained a legendary class?

In the year 54 of the Konoha Calendar, two super geniuses appeared in the Konoha. One is named Uchiha Itachi, and the other is named Akihara Kagura. One is a tool of the village, willing to sacrifice everything for Konoha, except for his brother Uchiha Sasuke; the other claims to be a tool of the village, also willing to sacrifice everything for Konoha, including Uchiha Itachi's brother, Uchiha Sasuke.

Huang Dan’s pain nerve is innately different from the ordinary people. A little tore in his skin can cause him to sweat all over his body painfully to the point of him unable to make a word out.

Somehow, he began to cross world, following Mr. System to do the tasks…

In the first world, Huang Dan realizes what it means to die painfully and to live to die again.

TL’s summary:
MC suddenly transmigrated and is bind to a system, requiring him to solve mysteries. Born with a higher degree of pain sensitivity, he met different people in the different worlds and learns what kind of emotion smiling is.

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