In-universe of Machine-Doll, the lubricants for the doll's eyes (that made it their tears, essentially) will crystallize when not in direct contact with the dolls' bodies. Basically without mana it will revert into solid form, much like when a doll 'dies' it will cease looking human-ish and reverted into life-size ball-jointed dolls. It also MIGHT have connection with Yaya's power of hardening parts of her body even those that is not in contact with her anymore. Source: http://kikoshojowakizutsukanai.wikia.com/wiki/Yaya
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It's SOOOOOO unforgivable for him to be engrossed in other women when he has already got Yaya!!!Nobody other than Yaya is suitable to be Raishin's wife...Raishin had affairs with a human girl!?Sob...sob...