You don't want to fap because she's depicted has more of a real little girl than what you're used to with you're Kodomo no Jikan. She's not sexualized, she's not a loli, just a little girl.
And part of the reason why the drama is more effective and you're feeling quesy (pansy) is that the dialogue is handled mcuh better than your average series. In most shows there's always a pause between when one character speaks and when another responds or even when they're interupted. It's hard to get any chemistry between actors and really hard to get any interaction between actors because they all record separately. Kurenai has a substantially shortend pause between different actors.