Emiko Niwa's husband is the shy and thoughtful Kosuke Niwa. He married into the Niwa family and adopted the surname meaning he himself
is not a Niwa male. He knows a lot about magic and had been journeying often, not having seen his son for many, many years
until he finally returned when Daisuke is 14. Kosuke left when Daisuke was only two years old. He is currently searching for
the secrets between the Hikari/Hiwatari and the Niwa family. He is very serious when he needs to be, but generally he seems
clumsy, exactly like his son (shown in the manga, having the same reaction as Daisuke Niwa's). He is easily embarrassed by his wife, Emiko and her antics. Kosuke was also one of the few characters who arrived late
into the series and his first family name is unknown.
Kosuke seems to be a logical thinker and has helped Daisuke in a number of ways in the story. In both the anime and the
manga he researches the fairy tale 'Ice and Snow' since it refers to Dark's target at the time, the Second Hand of Time ('Toki
Difference in the anime and the manga
In the anime he gives Daisuke a replica of a ring named 'Rutile' believed to enhance one's abilities. Later it is revealed
that using his own Kosuke was sharing the burden of Dark's magic with Daisuke.
In the manga he gives both Daisuke and Satoshi rings. Unlike the Rutile in the anime, the rings have an ability to allow
the wearer to revert from their alternate form, but works only once. Dark and Krad cannot take them off (much to Dark's annoyance).
Kosuke also gave Daisuke a bracelet with identical properties