It's only natural to find lolis cute. Your brains is programmed to find little ones of your kind adorable, innocent, in order for you to protect them from any dangers. You find little girls the cutest, because they are the most defenseless, in the biggest need for your protection. You want to see them be happy, secure, you want to see them grow up in calm and peace. If you don't, something is a little bit broken in your brain. While yes, lolis are only drawings, our brains are capable of seeing those drawings are little girls, therefore activating the same emotions towards them, as it would with a real girl.
It's even stronger if the petite girl is your daughter or you really consider her yours, but even without it, it's still apparent.