1) the name argenti - "argentum" meaning "silver". the color usually represents the moon (even though he as a knight wears the golden armor)
2) fictional "moon" type is usually given such characteristics as being emotional, feeling, intuitive, calm and sometimes introverted (in contrast to the "sun" type of sun-moon dynamic). i believe argenti is quite sensitive, perhaps dramatic (his performance on the express, going extreme while speaking of death and life purpose; he chooses to "enjoy the moment" knowing well some day he might lose to the Omen of Evil and meet his end) and reflected on his life choices more than once

argenti's devotion to beauty and all the bright colors and thousands of roses is impressive, of course. he's silly and cute and it's shown in reaction of other people on him, in his music themes and promo arts. but the tragic backstory contrasts with such behavior — he is more than flowers and sparkles. it's the patience and endless searches, willingness to serve, be outshone by something - or someone - brighter. he's about emotions, he listens to his heart, he's tender and careful when talking about feelings — that's what makes him the moon to me