Gakkou no Ojikan

Riku is just a normal high school student, but one day when she gets home she finds out that her grandfather has made her the chairman of a an elite school. At first she isn't very happy but when she meet two very cute guys things just begun to get interesting.

(Source: ANN)

Included one-shots:
Volume 5: Your Hands, Your Eyes (Kimi no Te to Hitomi to)
Volume 9: Gokuaku Drop