I think the phone conversation in EP4 reveals a lot. I'm guessing that these phone calls are a plot device to give the audience a chance to explore Sana's emotional state without making him look too emo.
On top of that, it seems as though he is very honest with his mother. He doesn't seem to glaze over when he talks to her. If he feels like crap, he sounds like crap. And he comes across as being comfortable with that only when addressing his mother. Plus, he's willing to ask her about somewhat embarrassing subjects. I'd say his relationship with her is far better than usual for an Anime lead. Forgive me for being an optimist.
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Now, can someone please explain to me why Aoi is still my favorite character even after Hinako shows up? Please! How can I live with myself if I prefer the massive-boob girl over the loli!?!?!? That's it... I'm going to marathon Chobits tonight to cleanse my pallet.
