Soul-Eater Ring

He crawls out of a pile of dead mine slaves, carrying an ancient poison in his body, and infiltrates an immortal sect.

He betrays his companions, takes a master, learns their arts, and slaughters his way to the top, eventually becoming the sect's leading disciple.

Everyone thinks this is a menial disciple's rags-to-riches story.

Until the day of the “Harvesting Ceremony,” when he tears off his disguise in front of everyone and bares his fangs at the entire sect.

“Thank you all for helping me reach the top.”

“Now, all of you will become my human pills.”