From Blissful Sin:

Growing in an orphanage, Keita had to work and pay for his tuition and for his home expenses. Starving with hunger he fainted later on the streets and was rescued by Kouzuki. Which turns out Kouzuki was a company president! Keita thought he found a solution for his problems so when he asked for a job, the kind of job he thought was not what he intended. Knowing no other way, he agree to be a playmate for Kouzuki. But what would happen if he'd fallen for Kouzuki...?