The question is too vague. The word familiar can be used in one too many stances for it to be translated into another language out of context. お馴染み /o na ji mi/ is one equivalent for it.
Wasu does not appear to be a Japanese word. I'm not familiar with it, and have checked multiple Japanese dictionaries to be certain. Perhaps this is a typo, or you have misread the kanji/kana.
He is familiar with the Japanese food as long as he lives there
君 Kimi being the kanji for the familiar form of "you". (In other words, it's the informal version!^^)
の君 is just a thing to tack onto a name with someone you are familiar with.
That is not a standardized romanization of a Japanese word, nor does it sound like any Japanese word I am familiar with.
Deniva does not mean anything in Japanese.
"Olga" is not a Japanese word or name, so it doesn't mean anything at all in Japanese. Did you mean, "What is the name "Olga" translated to in Japanese?"
The name 'Collin' does not mean anything in Japanese, but it can be written in Japanese as: コリン
Kaitlyn does not mean anything in Japanese, but can be written in Japanese as: ケイトリン
This does not mean anything in Japanese.
If you have a familiar spirit according to the Bible, it means that you are into witchcraft.
"Anata WA ijiwarui desu." This is the formal way of saying it. "Kimi WA ijiwarui da." This is the familiar way of saying it. "Omae WA ijiwarui da yo!" If you really want to be mean about saying it.