Sheng Kawolski

Sheng Kawolski runs the water purifier in Diamond City in 2287.

Background
Sheng, despite his age, throws his weight around with any adults he encounters, even calling the player character a "jackass" to their face if they refuse to buy the purified water which he peddles.

Daily schedule
During the day Sheng's in charge of Diamond City's water purifying system. If you go to the schoolhouse at night, you will see Sheng sitting at a desk doing night classes.

Effects of player's actions
He will replace Travis Miles as the DJ of Diamond City Radio should Travis be killed during the Confidence Man quest.

Other interactions
Upon first approaching Sheng, the Sole Survivor will find him arguing with one of the Diamond City guards about the purity of the water he's in charge of keeping clean. The player character can ask Sheng for work, whereupon Sheng will give the job of clearing the water around him of any debris that could clog the water filters. Among the miscellaneous junk the player must find is a human skull. When the job is complete, the player character can confront Sheng about this, which Sheng will casually reply that he may have sent someone else to do the same job before the player, and that perhaps that person found a live grenade.

Appearances
Sheng Kawolski appears only in Fallout 4.