Hentai Shitsuji kara Nigeraremasen!

The second son of the aristocratic and fabulously wealthy Tsutsumi Family, Haruto Tsutsumi, is being passionately pursued by Shou Natsukawa of the Natsukawa line, which has served the Tsutsumi house for generations. With an affection bordering on harassment, Shou follows Haruto after the young master runs away and takes up residence next door. Trying to kick him away only results in Shou offering up his head with the plea to "please step on it". It doesn't take long before Shou begins "servicing" Haruto without permission, and his unusual appeals seem to escalate more and more, until...

(Source: Gentosha Comics, translated)