Both protagonists are in essentially identical situations, where the main character are nearly clones of their counterparts in the series. They have the same behaviour, reactions, and similar appearance to the character(s) in the other series. Love Hina is probably more ecchi, but that's not saying Ai Kora isn't ecchi at all.
Both revolve around male protagonists who begin living amongst a number of female characters; most of which become romantically attracted to him in one shape or another. As such, romance and comedy are emphasised in both titles.
While Keitaro is often accused of being a pervert due to clumsy accidents and bad luck, Hachibei is the exact opposite: he's a bona fide pervert. This "Parts-lover" ends up, like Keitaro, at a girl's dormitory, with each of the girls there possessing one of his ideal parts. Hilarity ensues.
Both are the generic harem scenario where there is a guy surrounded by many cute girls. In Love Hina, it is more of a romance than Ai Kora (Love Collage). While Ai Kora has a more innocence sense to it. how Hachibe does everything he can to make the girls that he likes be happy. They both have this somewhat tranquility sense to it but both are great series with great unexpected endings.
A boy starts living in a dorm that consists of only GIRLS! Both series begin with the boy characters are misunderstood by the girls in the beginning that they're leeching perverts (although there is a slight difference, in Ai Kora the boy actually is a pervert but in Love Hina he isn't). Gradually over time both boys and girls in each series start developing feelings for one another and both go through a series of hilarious, heartwarming events and scenerios. If you love one, I can guarantee you'll love the other.
These 2 manga series are similar in their main male character (the happy-go-lucky cum idiotic kind but serious in times of need) and that both feature love triangles between the guy and 2 close friends.
However, Ai Kora is more focused on fetishes while Ayu Maru is about two girls who might be the guy's brother, and the other possibly his gf (which is similar to Onegai Twins).
Both are comedy-inspirational manga series, with 1 main super weird character. Inspirational as in the main character inspires others to fulfil their dreams, find their goals etc., but usually in a funny manner.
For Ai Kora, fetish is included but for Sumire it's rather a puppet and a puppet master.
the similarity between these two mangas isn't in the basis of their history but in the unusual comedy, both of them have a history comedy/romance, kind harem, about a guy having all kind of problems, for me this two is the best comedy mangas that i've ever seen.
Harem manga where the protagonist woos all the many girls, with plenty of romance, humour, and eroticism. Yet despite there being a main heroine or the one most favorited, he never ends up decisively choosing to enter a formal relationship with anyone, intentionally left ambiguous; a typical ending to most harem titles, but should have been expected from the start.
Given that these two series are authored by the same mangaka, there are many similarities. One of the obvious ones is how Hachibe and Iroha are essentially the same person. Art style, pace, and narrative structure are also similar.
Both male Leads have an Eye for the female Body and its special Parts, while Hachibe is just a parts Fetishist running Wild for the Girls with his beloved Parts no matter who it is, Ouji is a perv who is recruiting Cheerleaders for a Club with his Eye for the Body, making them Join who ever they are.