Well, as for me:

-Kidou X Haruna ( I know they are siblings but they look so cute together )

-Aki X Endou ( I like NatsumiXEndou first but I starting to like this better )

-Aki X Ichinose ( No offense, they are childhood friend and Ichinose hugged Aki once. He also meet Aki first in any situation )

-Tachimukai X Haruna ( Both are 13 and really friendly towards each other )

-Kogure X Haruna ( More like motherly love to me )

-Touko X Endou ( More like love-hate relationship but I'll call them close friend rather than couples )

-Reika X Kazemaru ( i know Reika only met Kazemaru at one episode but Kazemaru reaction is cute.)

-???