If you're looking for anime similar to Fortune Arterial: Akai Yakusoku, you might like these titles. All recommendations are made by Anime-Planet users like you!
The traditional girls-only Yuihime Private Academy is considering the possibility of starting to accept both genders and has thus made an agreement with a neighboring school to receive some of its students as an experiment to see the reaction to this adaptation. Shingo Iryu is one of the many students transferred for a ten month experimental phase at Yuihime Academy. He, his sister, and his fellow relocated colleagues are impressed by the sophisticated campus, but even more by the resistance of many students who don't want the boys over there.
Aside from being harem anime based off a visual novel, the story begins with a protagonist transferring to a new school. Eventually, he joins a club that acts as the center point where he will establish or build on his friendships, with the females in particular. The main heroines hold this club very dear to their hearts, and with the assistance of the selfless protagonist, their collaborative actions in the club better the lives of living beings. Romance also blossoms while working together.
Freshman Kurogane Taito was always an ordinary, regular guy, except for a promise made to the beautiful vampire, Saitohimea nine years ago.
Both of these anime involve vampires (though Fortune Arterial is more vampire-focused, whereas Itsuka Tenma no Kuro Usagi has other fantasy elements as well). They both spend quite a bit of time on things not directly related to the main conflict - such as romance and school life. Both have school as a central setting. And, of course, both seem comfortable with bits of fanservice here and there. Though that last bit could be a turn off if you're anything like me.
The art is similar - fairly bright and bishoujo. Unlike most other vampire anime, these two steer away from a very dark atmosphere.
Granted, I only made it halfway through Itsuka Tenma no Kuro Usagi, but I'm fairly confident thant fans of one anime will like the other.