Risa is a girl, but despite this fact she is really tall and always was been laughed at. She meets a boy named Otani, who is way shorter than average boys. Those two make the comedy couple in their class, as they are always fighting with each other. And little by little they become good friends with each other, developing romantic feelings.
Falling in love in a similar way, characters getting closer, relationship from hate to love. I must say that at the beginning even the plot is the same, but it changes over time. And there is some great comedy in both.
The two series are quite different, however they both have a similar humor at times. I believe that one who enjoyed the comedy moments in one would like the other as well. The two series are both less considered as 'romantic' but mostly deal with comical situations while involving a little bit of romance here and there.