Well, one difference could be the art style. Maybe haa haa manga has a more distinct or appealing visual approach. Also, the themes explored could be different from other similar manga.
The main features of cartoon animal clothes lines are the charming animal motifs. Styles can be playful and child-friendly or trendy and suitable for adults. Sometimes, they combine different elements like stripes or polka dots with the animal images for a unique look.
The combination of the angel's purity and the devil's allure in a love story is what makes it so appealing. It explores themes of forbidden love and defying expectations, which draws readers in and keeps them hooked.