Ferio wandered Cephiro for most of his life all alone. When a shy, cute girl entered his life, he developed a crush on her instantly. Although she acted like she wanted nothing to do with him, he didn't give up, and it wasn't long until he was in love with her and able to get her to open up to him.
Hououji Fuu is polite, reserved, level-headed, logical, and serious, withdrawn in her school work. She doesn't have many friends, but when she came to Cephiro, she got two friends and a boyfriend. She seems the most unlikely to fall in love with someone she hardly knows, but she does.
hush... the wind whispered as the sun broke the silence of the night and brought forth the sparkle of the morning dew
isn't that pretty? It explains Ferio and Fuu's relationship:
The sun represents Ferio: bright and showy. The night represents Fuu: quiet and reserved. The wind encircles them and is also Fuu's magick. And the sparkling morning dew represents their love.