[Connor leaned forward, squinting a little to watch as she licked the screen. That was... odd.] You can't taste me through a screen. [Still. He hoped he didn't taste too synthetic in person.]

CyberLife wanted androids to integrating seamlessly among humans and their designs incorporate small flaws - freckles, moles, facial hair - in order to avoid the uncanny feeling you're referring to. This was partially why the Android Act was passed, requiring all androids to wear an LED ring, among other things, in public to identify them and distinguish them from humans.

[Alright, so that didn't exactly answer her question. He'd more or less told her what CyberLife did and not why they did it... mostly because he wasn't completely sure. He assumed it likely had something to do with all of the various functions androids were purchased for. Just let your imagination run wild, Terezi.]