DiaRuby

DiaRuby is the family ship between Dia Kurosawa and Ruby Kurosawa from the Love Live! fandom.

Canon
Ruby and Dia are sisters who seem very much different save for their green eyes and love of school idols. Ruby and Dia used to have lots of fun talking about school idols together. They would dress up and sing, and read magazines together. Then, after Dia entered high school, she suddenly despised them for a reason Ruby didn't understand and didn't let Ruby enjoy them around her. Ruby felt like she needed to hate school idols too, even though she loves them, because she can't keep liking something her sister doesn't.

Dia is against the School Idol Club, especially Ruby joining it, but it passes anyway. Dia watches Ruby's clip of Aqours "Fallen Angel" video, and says it's shameless. She is angry that they dressed Ruby that way and made her do this. Ruby says she's sorry.

One day Ruby visits Dia at the student council to tell her she's going to be late coming home. Dia asks why, and Ruby says it's because she's going to make a PV with the other idols. Dia doesn't counter it, to Ruby's delight. Chika finds out Dia used to love school idols, and goes to say something to her, but Ruby stops her from doing so, because she still wants to respect her sister's space.

Ruby tells Dia about the offer Aqours received to perform in Tokyo. Ruby asks if her being a school idol is bothering her. Dia says that since Ruby decided to be an idol all on her own, it doesn't matter what anyone else thinks. Later, before Ruby heads out, Dia tells Ruby to stay strong. As it is later told, Dia was opposed to Uranohoshi having school idols due to her failure as one when she was a first-year. Nevertheless, she respects and supports Ruby's choice.

After returning home from their trip in Tokyo, Dia comes to greet Aqours. Upon seeing her sister, Ruby squirms around a bit before diving into her sister's arms and crying. They go to a more comfortable spot when Ruby rests her head in Dia's lap and Dia strokes her head, making her feel calm.

When the summer season rolls around, Dia asks the group what summer vacation means, and asks Ruby to tell. Ruby says it means Love Live!, and Dia gets overjoyed, rubbing Ruby's head and saying she did a good job in a baby voice. Later at the beach shack, when Ruby eats Yoshiko's "tears of a fallen angel", which is very very spicy, Dia angrily asks just what she put in them. At night, Dia and Ruby sleep with each other at camp.

Moments

 * S1E09: At separate times, both get pressured to tell a secret and then get flustered and run away, only to be thwarted by Yoshiko's arm and leg lock. Both cry out with their hand stretched out in the same way.
 * S2E11: The two run a game show together.
 * Movie: Ruby is relieved to see her sister again, twice.

Fanon
DiaRuby is a popular familyship in the Love Live fandom since the two sisters are main characters whereas other family ships usually involve a side character instead. Much of Dia and Ruby's relationship is explored and their deep bond is made apparent. Many think that Dia's overprotectiveness for her sister and Ruby's great love and respect for Dia is very nice. They are occasionally shipped romantically, although it doesn't receive much positive recognition when done so.

Fandom
FAN FICTION

PIXIV

TWITTER

Trivia

 * They have a duet called 
 * They are both named after gemstones.