Total Recommendations: 2
Much like Shouwa Genroku Rakugo Shinjuu, Sakamichi no Apollon is character driven. It focuses on the daily machinations of its characters and the art form they practice. The time period and tone of both shows are extremely similar and they both have that cool, mature feeling.
Both series explore the taboo nature of humans interacting with a different being. In the case of Hana to Akuma, it explores the relationship between humans and demons, while Monokuro Shounen Shoujo explores the relationship between humans and beasts. The female and male leads are very similar in personalities and appearances. The overall tone of both manga are also the same. With that said, the two series are similar enough to resemble each other, but are different at a lot points. You definitely won't feel like you're reading Hana to Akuma a second time. But if you liked the tone and characters in Hana to Akuma, you'll probably also like Monokuro Shounen Shoujo.