Funeral, what should I do if I reincarnate as a demon?

He was reincarnated and became a demon with extraordinary talents and a long life span.Although he became an orphan with living parents at birth, he had to fend for himself and be careful of his own people and humans, but it didn't matter. At least he suddenly had a system when he was three years old, but the system was unexpectedly not very useful.But it still made him go back to the past, made friends with Fulilian, and became the junior of the ancestor of human magic, but he soon discovered that this friend had a big prejudice against the demons.It's okay, fortunately, the little sister of the tribe who I knew since birth-Aura has become successful, but... when I was a child, I often ordered her around, so the relationship is a little subtle.The problem is not big, he also knows the strongest hero, but... the other party died a little early.Just jumping back and forth between humans and demons, he gradually found that it seems that there is no side that can be relied on."There is no way, I still rely on myself."He set a new life goal for himself-kill the current demon king! Become the new demon king-tentative.Author's Other NovelsA super traveler in a peaceful world