From Nakama:

Every day, high-school student Hanamura Naoyoshi is challenged in his part-time job as a helper for the aged.
But one day - suddenly - a request comes from Sadamitsu Norihiko, an heir to a large enterprise, for a helper for someone recovering from sickness.
From the first day, a bewildered Naoyoshi swears obedience, but their attraction is immediate, and the two share a kiss.
But, suddenly, communication comes to a halt and they're no longer able to meet, and when they do meet again, Norihiko has completely changed into another person.
A heart-trembling, sensitive love story!