Sapphirus and her Dialga, as a semi Christmas card kinda thing. Sapphirus (Me) LOVES Dialga, their colors and glows are similar to Sapph's color scheme and glows. Kyogre is her other fave. So this special Dialga was named, well after her....ego alert. She gifted her partner the power to change into a shiny when he wants, so sometimes he's shiny, sometimes not.
(I love Dialga's general color, but I also love shinies too so I dont wanna have to decide on a shiny dialga too. (2 Dialgas) LOL.)