Ohana to Chocolate
お花とチョコレェト
In the Taishou era a rich family's son picks up an orphan boy and fosters the boy into a little prince. He finally takes the boy abroad to find the boy's English father who abandoned him.
Extra story: the hero consults a mysterious girl by cellphone about his one-sided love. But the girl turns out to be his one-sided lover...
(from B-U)