ARIES
The Ram
The one that talks the most with Azura, exchanging light, small words that are little but collectively pile up into something so meaningful is Sakura. The one that defends Azura in court when nobles talk behind her back, using whispers loud enough for sharp ears to catch easily is Ryoma. The one that taught Azura the wonders of flying on the back of a winged horse, high up in the sky is Hinoka.
Out of all four of them, however, it's actually Takumi that spends the most time with Azura. He's the one that keeps an eye out for her when she wants to sing next to her lake. He does it from a distance – far enough so that he can keep himself out of her sight and give her a sense of privacy, but close enough so that he can hear her sing, and step in should anything dangerous threaten her.
Hoshido has not accepted Azura as its princess, in place of their missing one. Takumi cannot speak for his other siblings, but he has not accepted her as his sister.
Whatever Queen Mikoto has said about her being treated like a princess of Hoshido, it is not safe for a royal in only name, unaccepted by any save for a very select few, to go around alone without a retainer to protect her when there are many who harbor ill will towards her and what she represents.
(Failure. Loss. Murder. Betrayal. Abduction. A price not yet paid back in the currency of blood.)
Takumi always makes sure to follow her when she slips away from the palace and all the people looking at her, but he steps lightly, the breeze of Fujin Yumi letting him step as silent as a ninja through the forest, and does not let her know what he does.
There will be dissent and dissatisfaction when a noble family is punished for an attempt to – hurt? Kidnap? Kill? – a hostage from a hostile nation, but there can be no complaint when the second-in-line to the blessed throne of Hoshido and the wielder of the divine bow is the one supposedly threatened in the attempt.
If she knows what he does, when she looks at him with gold eyes framed by hair the color of lake water, eyes that are older than her age and speak of knowledge deep and vast, she does not say. If she knows why he does what he does, she doesn't give any signs of knowing it.
She's always been perceptive, but she doesn't say, or ask. And though her gaze leaves him flustered and uncertain with his words, he won't be the first to admit it.
Takumi cannot speak for his brother or sisters, but he has not accepted Azura as a sister. No brother looks at his sister the way he looks at Azura.