as you may have guessed, right, Tetsuya Yukumi.
source:
Te-chan's official site:
http://www.ztv.ne.jp/phsh9fn3/
In the BBS, someone asked him if About You was composed by him, and he said "Yes!". But for some reason, it seemed that he didn't know the existence of "CAROLS"...
Edit: OMG, he denied that he composed About You on his BBS......
