Humanoid harem - Kissing makes them stronger So there was this anime I watched but never finished and I forgot the name of it. 

The anime was a harem, and the story was about humanoids fighting each other until only 1 survived. All the humanoids were girls and had the power to become stronger if they kissed a person. 

A few things I remember: 


Humanoids 1-9 (possibly 1-10) were stronger than the rest. 
At one point, the main character helps a man and his humanoid escape the city (a forbidden act) which was heavily guarded with a few of the 1-9 humanoids. 
The main character's sister had a humanoid that was trying to find it's sister, which turned out to be the main character's humanoid. 


I'm sorry if this is confusing but it's probably the most simple way I can put all this down. I'm 99% the girls were some type of humanoid or something but I'm not 100% if the term in the anime was humanoid.
Probably Sekirei. 


  the story was about humanoids


Which are called "Sekirei".


  All the humanoids were girls 


Most, but not all (Shiina is male; Homura may also be). Equal-opportunity fanservice!


  the main character 


Generic McProtagonist-kun.


  helps a man and his humanoid escape the city


Shigi with his Sekirei, Kuno.


  the main character's sister had a humanoid that was trying to find her sister which was the main character's humanoid


sister = Yukari; her Sekirei = Shiina; Shiina's sister = Kusano; Kusano's "master" (Ashikabi) = McProtagonist-kun.