Kaku Seiga Correct "Ga", meaning "Beauty"

Ga (Beauty): Good-looking. Beautiful.

Kaku SeiMoth

Ga (Moth): Nocturnal Insect resembling a Butterfly.

Kaku SeiCliff

Ga (Cliff): Steep side of a large rock. Cliff. This is an uncommon Kanji. More details here.

Kaku SeiMountainous

Ga (Mountainous): Towering Mountains

I cleared Magical Astronomy on Lunatic. Magical Astronomy is, of course, a Music CD

Kaku SeiSecondary

Ga (Secondary): Bandwagon fan. While this kanji typically means "abrupt" or "sudden", here it's used as a slang term to mean a newcomer fan who jumped on the bandwagon. As in "Niwaka Fan". See more here .

I haven't been seeing you lately...

Ga (Desire): Not receiving what you longed for makes you want it even more. This Kanji typically means "Hunger", but the artist used it in a more metaphorical sense

Kaku SeiDesire