for save him
黒い息子 /ku roi mu su ko/. If by black you mean of African American descent, you can say 黒人の 息子 /ko ku jin no mu su ko/.
hindi ko alam
wag nyo ko tanungin di ku nga rin alam ehh
baduyan ampatuan spikinisan
Malay ko d ku alam .... ?? Haba kc ng kuwn2 nakkbobo ...
美しい子ども (utsu ku shii ko do mo)
暗黒の王子 /an ko ku no o jou/ is Japanese for 'Prince of Darkness'.
鼓腹の追撃 /ko fu ku no tsui ge ki/.
'Stranger(s)' in sense of 'foreigner(s)' would be 外国人 /gai ko ku jin/ and also 他国人 /ta ko ku jin/. In sense of 'unfamiliar person(s)' it would be 知らない人 /shi ra nai hi to/.
王 /ou/ is the kanji for 'king, ruler'. It is usually used as 王さま /ou sa ma/ for respect/formality. Specifically for 'ruler, sovereign' esp of a country 国王 /ko ku ou/ or 国主 /ko ku shu/ is used. Other word/variant for 'king' would be 王者 /ou ja/.
黒い騎士 /ku roi ki shi/. If by chance you would mean a black person by 'black' that would be 黒人の騎士 /ko ku jin no ki shi/.
As a name it can be both ティコ /ti ko/ and less commonly チコ /chi ko/ (Japanese don't originally have 'ti' syllable, instead they use 'chi'). As the name of the impact crater on moon it is ティコクレーター /ti ko ku ree taa/ meaning 'Tycho crater) or in short just ティコ /ti ko/.[ee = elongated 'e' sound]