These characters mean "both of you" in Japanese: 貴方達.
'Uchiki' and 'hajirai' are both Japanese for shyness, bashfulness.
You can say "Ojou-Sama" or "Ojōsama" either way.. you can say both.
リーヴァイ /rii bai/ and レビ /re bi/ are both Japanese for 'Levi'.
'Momo' and 'futomomo' can both mean 'thigh'.
Both the name and the bird are ロビン and is actually spoken as 'robin'
'Kowai nagara doujini tanoshikattan desu'.
'Shiroi ookami no koushou/kamikizu" is the translation of that phrase into Japanese. (Both koushou and kamikizu can be used)
教授 /kyou ju/ means 'professor' in Japanese used both single and as a title e.g. after a name.
'5 days' may be either 五つ or 5つ in Japanese. Both are pronounced as 'itsutsu'.
Shiwa (皺) This should work for both clothing and facial wrinkles.
速さ /ha ya sa/ and スピード /su pii do/ are both very common words for 'speed' in Japanese.
To say old Japanese illustrations in Japanese, you say "Mukashi no Nihon no irasuto".