The Great Sect Who Emerged from the Demon Sect

Li Xingyang, an upright young man, traveled through time and picked up a master who was said to be extremely powerful, and a fairy sister with great beauty and extraordinary talents. However, both master and senior sister are demons, and master is even more of a big demon! How does this make Li Xingyang, who once represented justice, deal with this? I, Li Xingyang, am a great righteous person from the Demon Sect!