Comedy/school life/shoujo

After their parents are killed in a plane crash, Ryuuichi and his younger brother Kotarou are taken in by the chairman, who they never met before, of an elite academy. Ryuuichi becomes the school daycare's new babysitter.

I've read it and I love it. It's cute, light-hearted, and fun to read. There's 6 chapters so far and look forward to more.