忠 loyalty

You're so loyal I could kiss you *CHUU!*

Your loyalty makes you central to my heart.

faithful ★★☆☆☆
忠 (loyalty) + 実 (truth) = 忠実 (faithful)

someone who is faithful in doing his/her duties. Also means like a movie which is faithful to the book, or a translation which is faithful to the original. Or even a forgery which copies the original dollar bill completely well.

admonish ★☆☆☆☆
忠 (loyalty) + 告 (inform) = 忠告 (admonish)

admonishing negative advice: "Don't open that door!" "Don't swim naked!"