Firstly i felt the same but i consider this reason for their jodi: Romi knows Sarika is Not that good in terms of looks... but he is showned to Like her nature..personna.. heart... Thats why he doesnt check her out...like he does with other girls... Sarika is supposed to bring Love out of Romi.. n Love is not bound by looks
I like the Romi-sarika jodi they look cute together...sarika looks good with romi and even individually also...in the show sarika has been shown as a simple girl so her appearance is simple in terms of dress and make up...