Martial Legacy is a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

A boy named Shi Shan along with his little sister were offered as sacrifice to a demon that has been haunting their village. They were rescued by a martial artist who exorcise demons. He took the siblings in as his disciples and taught them the art of cultivation and about the demons that dwell in this world.