Kaichou-san no Koneko

From Shoujo Crusade:
Because of his much-too-strict character, the excellent and capable student council president, Hayami Reiichirou was isolated from his surroundings. But, one day, he is forced to take care of a kitten he received from his mother who is in the middle of divorce. Seeking help from the resident cat-lover in the student council, Shiraishi Kotoko, there is...!?

Also contains, Gakuran Ouji.

From Omari's Sister:
Uptight Student Council President Reiichiro Hayami gets dragged into taking care of a kitten. How will the adorable kitten, Ku, change Reiichiro's life?