Dark Angel in Chinese / Japanese...

暗天使 is the shortest way to write, “Dark Angel,” in Chinese.

This literally reads, “dark heaven's messenger.”

天使 means “heaven's messenger” but is always understood as “angel.”

This would be pronounced "kura tenshi" in Japanese. This has the same meaning in Japanese, but not a common title. If you manage to find dark angel written in Japan, it would probably be ダーク エンジェル (Dāku Enjeru), which is a transliteration of the English title into Japanese, or 暗い天使 (kurai tenshi) which is a specifically Japanese title.

暗い天使 means “Dark Angel,” in Japanese.

The first character means dark, gloomy, hidden, or secret.

The second character is a connecting article.

The last two characters mean angel.

黑暗天使 means “Dark Angel” in Chinese.

The first character means black, but the second means dark by itself, so this can also be written with the first character dropped.

The last two characters mean angel.