Crow, the loyal butler of a villainess, realizes through a series of chance events that he has in fact been reincarnated into another world.

With a new perspective on life, he realizes just how badly he's been treated by this haughty, egotistical and prideful noble lady he calls his mistress until now, and boils with rage at the injustice.

However, after deciding to take revenge on her in a risque way, he comes to realize that she's a lot easier than she looks...

This is a story of how a reincarnated butler tames his villainous mistress in lustful ways, but ends up making her truly happy.

Note: Original language image is unavailable.

From Infinity Studios:

When you're the most notorious delinquent at school you have one hell of an image to maintain. The last thing you need is to be seen taking orders from an innocent puppy-eyed girl. But unfortunately for Keiji Sendai, he finds himself in this exact predicament when, Setsuna Yatsusaki, the shyest girl in school (as well as being the biggest klutz) finds out about Keiji's deepest and darkest secret... that he's a hardcore otaku! With her new trump card, Setsuna blackmails Keiji into becoming her slave. But just how long can a weak naive young girl keep such a dangerous young man as her pet dog? Join in on Setsuna's secret as she sets out to "train" a notorious thug in this unorthodox love story.

Note: Was originally serialized in Dengeki Teioh magazine in 2005 as "Kyouhaku Dog’s". This run ended after the magazine became defunct in 2006.
Serialization restarted in 2010 issue of Dengeki G's Festival! Comic under the title "Kyouhaku Dog’s - Another Secret".