The first sentinel he meets is, of course, in their fight against Mugen.

He and Hiroto had made their way, easily, through what he later learns was over a hundred men, to the leaders.

The blond - Cobra - is a sentinel and naturally the leader - Kohaku - is too.

The blond and his companion are young, not truly a match for them, proven further when the two leaders jump in to fight 4 v. 2. Even then they aren't enough for his and Hiroto's combined efforts.

If Aniki was there, it wouldn't have even been a fight.

But he was off doing his own thing, securing their next job and Masaki finds himself in a fight against the older sentinel. Their fight ended in a tie only when the police - Saigo that bastard - came and Mugun scattered. Hiroto pulls him from the fight as the other Mugan leader grabs for Kohaku. The look in the older sentinel's mismatched eyes promised this wasn't over and Masaki couldn't help but look forward to their next fight.


It's not long after that that things change again.

When Aniki begins to distance himself, Masaki notices immediately.

He can sense the subtle changes in Takeru as he begins to pull away.

He lets him at first, thinking Aniki only needs some space from his sometimes overbearing younger brothers.

Within a month, Hiroto has noticed too.

They quietly discuss it, not so much in words as emotions. They agree to give Takeru a semblance of space even as they watch closer than before.

When Takeru disappears, it takes Masaki an hour to find him. He traces his brother's heartbeat on foot through the streets, Hiroto a silent shadow. They watch from afar. Still wishing to respect their brother's space. Hiroto almost lunges for Takeru when the first of the gang members grab at him. Masaki, following instinct alone, holds Hiroto back. He pulls him tight against his chest as they watch Takeru. When his Aniki doesn't move to fight them, Hiroto settles against him, following his lead.

They watch for a while before heading back; Takeru can handle himself.

They sit up that night, waiting for him but Aniki doesn't return.

Everyday that week, Masaki follows his heartbeat to Takeru and watches from the shadows. He and Hiroto decide to let Takeru do as he wishes, assured by the emotions they can still feel from him. Masaki appeases his instincts by telling himself that Takeru is just on a solo job, if he needs them, Aniki will let them know or Masaki will sense it.

Watching every night becomes every other night, then only once or twice a week as time drags on.

He learns a lot from hiding in the shadows, taking pictures and identifying the people surrounding his Aniki.

Connecting the dots after that is easy.

Takeru is out for revenge on the Kamizono family of the Kuryu group.

For killing their parents.


With Takeru on the inside, Masaki and Hiroto focus on learning what they can to help him from the outside.

They research the Jurya group.

All of it's families.

All of their members.

Gradually, they compile lists of activities, movements, and actions that the group has taken as parts and as a whole. They dig up as much dirt as they can on as many of them as possible.

But mostly they spend a lot of time on the Kamizono family, on Uezono.

They don't know how much Takeru knows but they don't want him in the dark about anything.

Making sure he's not followed or seen by anyone Takeru's involved with, Masaki drops a big envelope of copies of everything they managed to dig up, documents, photos, everything, coded in a way that only they know, of course. He leaves it in one of their old spots, close enough to Takeru's new place so as not to be too suspicious for Takeru to get. The rest, making sure Aniki actually knows it's there, he leaves to Hiroto who pushes a message made of thoughts and emotion towards Takeru's shields.

Aniki's easy welcoming of the message is evidence enough that Takeru has felt Masaki's presence nearby and knows they have been watching.


Days later they receive a brief message back, gratitude and fear caution in equal parts.

Months later, Takeru leaves a package of his own.

A flashdrive.

Masaki watches for days, so attuned with Takeru he could feel his every emotion, track his every step, waiting to see if his cover was blown.

Luckily for them, Kuryu only had a few sentinels in the whole group and only one or two that promised trouble. When the Kamizono group starts cleaning house trying to find the traitor and the flashdrive, Takeru vaishes. Reappearing a few days later at their apartment. Masaki, who had heard his heartbeat getting closer over the hours, silently makes his way outside to the high rooftop of a building close to their apartment. He ignored Hiroto's curiosity pushing at him and settled down to wait.

If Takeru was being followed he'd have to step in before they reached their home.

His instincts prove true.

Aniki had a tail, far enough away that Takeru hadn't even noticed. But Masaki could tell by the way they moved, the way they held themselves, the way they stank of the same filth as their leader.

Masaki darted down the streets, bypassing Takeru entirely, he began hunting the men who dared to follow his guide to their home.

Taking them down was easy, even their guns were no match for a pissed off, overprotective sentinel hellbent on guarding his territory, his family.

He felt Hiroto's elation long before he got back and knew from his brothers' heartbeats that they were together once again.

Eventually, he settled back down on the rooftop, his instincts refusing to calm, not even for a moment to greet his Aniki.

If Kuryu had managed to follow his brother that far, they weren't safe.

He stayed there for the next two days and two nights, afraid to let his guard down enough to even sleep; resting his eyes but focusing the rest of his senses on his surroundings when it became necessary.

On the third day, Takeru and Hiroto came out to get him.

He felt them stirring, heard them moving closer as they climbed the stairs to meet him. Masaki stayed focused on the streets below him even as the gentle thump of two hearts beating in sync drew ever closer. The door to the roof opened behind him, his brothers stepping out to join him.

When he didn't turn to them, his brothers got closer, sliding to either side of him against the ledge of the building. His instincts screamed at him that they were too exposed, too hard to protect from the shots of their numerous enemies.

He turned, sliding a careful arm around each of his brothers as he herded them away from the ledge and off the roof. Just inside the door, Masaki releases his brothers, instincts demanding he return to keeping watch.

His brothers don't let him leave, Takeru pulling him into a hug. Hiroto settles against his back, warm and comforting.

For a second, Masaki lets himself bask in the shelter of his guides, shoving his instinctive protectiveness back to reassure himself of their continued survival. He nods at his Aniki's whispers of gratitude, emotions conveying what words cannot, I'd do it all again, over and over and more for you.

Eventually he pulls away from Takeru, moving backwards into Hiroto's embrace. Hiroto, who doesn't let go, instead curls even tighter around him and holds Masaki to his chest.

He lets Hiroto do as he pleases, never one to deny his guides anything and looks over his older brother. He'd been watching Takeru from afar for so long, it was good to finally have him close again. He checks his brother over, scanning over his body as he looks for injuries. His Aniki looks good though, looks healthy, looks like he actually got some sleep for the first time in months.

Reassured of Takeru's continued survival, he focuses on their surroundings again, making sure no one had gotten close. For a second, he loses himself in the sounds of the streets before being brought back by the gentle kiss Hiroto placed on his neck. Masaki refocuses on his guides, "Lets go."

He lets Hiroto lead them back to their apartment, keeping Takeru close to him as they move. Aniki huffed at his protectiveness but didn't argue, knowing they should be thankful for getting Masaki to leave his guard post at all when he still like this; more sentinel than his younger brother.

Once safely inside, they move into Takeru's room to discuss what their next move would be.

They had a flashdrive of dangerous information and a family to avenge.