Manga The Ballad Of Sang (2018)

Kidnapped off the streets of the Philippines as an infant and trained as a child assassin, Sang has never had a childhood. All he's ever known is killing and the kindness of his master, Chen, the closest thing Sang has to a father. When Sang's enthusiasm botches a job, it brings the wrath of Don Minchella down on the pair, resulting in Chen's murder. Barely escaping with his own line -- and with Minchella's severed arm in tow -- Sang swears revenge, while every gang in the city mobilizes to return him to Minchella, dead or alive.