Ability Stealing Hunter is a Manga/Manhwa/Manhua in (English/Raw) language, Manhua series, english chapters have been translated and you can read them here. The Summary is
Many years ago, the secret portal began to appear on the earth, and human beings have an additional occupation: hunter. Although the upper limit of the level that everyone can achieve is different due to differences in talent, compared to most ordinary occupations on earth, the income of hunter is objectively more, especially the income of high-level hunter is higher. It is enviable, so more and more people began to join the team of hunter. And the male protagonist is the unluckiest hunter in history!