Why does the Yoshida household have meals on the box where Joshua is sealed? Before chapter 25 the justification is poverty, and afterwards, the magical coating. However, when one reflects on how Lilith actually gets offerings, one would realize there's another very important reason: they're offering food to Joshua.
The reason the narrator always cheers Yuko up with "Ganbare!" is that Joshua said this a lot to Yuko before he got sealed, which makes a lot more sense when one looks at Chapter 36-38 which show the gravity of Yuko's health problems: she was dying at the time. This should explain why Joshua says this to Yuko a lot, as one of the several meanings of that expression is "Don't give up!"
Of course Anri would know about a restaurant run by a Demon. Her family's butcher shop has probably been making deliveries to it for the last ten years! And considering Shirosawa recognizes Anri, this is likely the case.
Metako is surprisingly friendly towards Yuko, and even more so for Ryoko, given that he's a Light Clan Navigator and they're demons. Then again, one needs to consider that Yuko contains the core of his former master, and Ryoko has significant potential to be a Magical Girl. Zikiel tries to capitalize on this at the end of volume 5 by offering to make Ryoko a magical girl, but she's too smart to go for it and sics Sion Ogura on him.
It actually wasn't so bad, as even despite her young age she was a well-off and well-meaning Magical Girl nonetheless. The entire Suika thing was bad enough as it was, as it really was rather traumatic and bleak, but she still holds that memory. The memories she doesn't have? Part of an unknown Ukrainian institution that had made her into a Child Soldier, where apparently their instructions were to kill themselves to prevent capture. And Momo was the Sole Survivor. Even if those memories were erased, literally everything about her childhood was a nightmare, to the point of not even having a name.
When Yuko first generates a magic effect, it turns around and tries to re-merge with her. She is told that it will hurt as much as an intramuscular injection to which she says 'that's one of those that hurt a lot, right?' When it does finally hit her, she yelps a bit but takes the pain rather well. Later, we learn she spent her youth in the hospital where she probably was continually getting intravenous and intramuscular injections (or blood draws), so she was used to that level of pain.
In a later chapter as she shows off pictures of her hospital years to other schoolgirls at a mixer, she specifically brings up that the hair they're complimenting was a wig. The Light Clan's curse was so powerful on her body, especially with the double-dosage of it by absorbing Ryoko's amount, it was akin to radiation sickness and rendered her bald from the treatments.
Momo actually encounters this thought herself later on even if she doesn't embellish on it: Yuko is effectively a Delicate and Sickly girl still slowly recovering from what would've been a fatal, terminal illness that was completely out of anyone's control and could only be suppressed by Sakura's core. One that Momo, without a single consideration except for how weak Yuko looked, put through Training from Hell to try to strengthen and muscle her up. Momo feels horrified as is, but the fact is that without her sheer life's fortune coming around, Yuko would be dead right now, and over-straining Yuko's core or demon powers could be intrinsically fatal rather than merely disabling.
